Significant Accounting Policies (Policy)	12 Months Ended
Dec. 31, 2015
Policy Text Block [Abstract]
Business Description and Basis of Presentation	The Company - National Health Investors, Inc. ("NHI" or the "Company"), a Maryland corporation incorporated and publicly listed in 1991, is a real estate investment trust (“REIT”) specializing in sale-leaseback, joint-venture, mortgage and mezzanine financing of need-driven and discretionary senior housing and medical investments. Our portfolio consists of real estate investments in independent, assisted and memory care communities, entrance-fee communities, senior living campuses, skilled nursing facilities, specialty hospitals and medical office buildings. Other investments include mortgages and notes, marketable securities, including the common shares of other publicly-held REITs, and a joint venture structured to comply with the provisions of the REIT Investment Diversification Empowerment Act of 2007 (“RIDEA”). Through this RIDEA joint venture, we invest in facility operations, managed by independent third-parties. We fund our real estate investments primarily through: (1) operating cash flow, (2) debt offerings, including bank lines of credit and ordinary term debt, and (3) the sale of equity securities.
Consolidation	Principles of Consolidation - The accompanying consolidated financial statements include our accounts and the accounts of our wholly-owned subsidiaries, joint ventures, partnerships and consolidated variable interest entities ("VIE") where NHI controls the operating activities of the VIE, if any. All intercompany transactions and balances have been eliminated in consolidation. Net income is reduced by the portion of net income attributable to noncontrolling interests. A VIE is broadly defined as an entity with one or more of the following characteristics: (a) the total equity investment at risk is insufficient to finance the entity's activities without additional subordinated financial support; (b) as a group, the holders of the equity investment at risk lack (i) the ability to make decisions about the entity's activities through voting or similar rights, (ii) the obligation to absorb the expected losses of the entity, or (iii) the right to receive the expected residual returns of the entity; or (c) the equity investors have voting rights that are not proportional to their economic interests, and substantially all of the entity's activities either involve, or are conducted on behalf of, an investor that has disproportionately few voting rights. We apply Financial Accounting Standards Board ("FASB") guidance for our arrangements with variable interest entities ("VIEs") which requires us to identify entities for which control is achieved through means other than voting rights and to determine which business enterprise is the primary beneficiary of the VIE. In accordance with FASB guidance, management must evaluate each of the Company’s contractual relationships which creates a variable interest in other entities. If the Company has a variable interest and the entity is a VIE, then management must determine whether or not the Company is the primary beneficiary of the VIE. If it is determined that the Company is the primary beneficiary, NHI consolidates the VIE. We identify the primary beneficiary of a VIE as the enterprise that has both: (i) the power to direct the activities of the VIE that most significantly impact the entity's economic performance; and (ii) the obligation to absorb losses or the right to receive benefits of the VIE that could be significant to the entity. We perform this analysis on an ongoing basis. At December 31, 2015, we held an interest in four unconsolidated VIEs, consisting of 1) a start-up lessee in which NHI's variable interest consists of its leasehold interest, analogous to a financing arrangement, and of which we concluded that NHI was not the primary beneficiary (Note 2); 2) our joint venture in an operating company organized under provisions of the REIT Investment Diversification and Empowerment Act, (“RIDEA”) of which we concluded that NHI was not the primary beneficiary (Note 3); 3) a note receivable from, a guarantee on a letter of credit for, and a purchase option with, an unconsolidated VIE of whom we concluded that NHI was not the primary beneficiary (Note 4); and 4) two construction mortgage notes receivable aggregating $83,411,000 from an unconsolidated VIE of whom we concluded that NHI was not the primary beneficiary (Note 4). Our direct support of the above VIEs has been limited to the transactions described herein, including our commitments and contingencies described in Note 8, and any decision to furnish additional direct support would be at our discretion and not obligatory. We believe our exposure to loss as a result of our involvement with these unconsolidated VIEs would be limited to our carrying value of these investments and the amount of our commitment as guarantor under the letter of credit. Generally, we lack, either directly or through related parties, any material input in the activities that most significantly impact the economic performance of these entities. We apply FASB guidance related to investments in joint ventures based on the type of controlling rights held by the members' interests in limited liability companies that may preclude consolidation by the majority equity owner in certain circumstances in which the majority equity owner would otherwise consolidate the joint venture. We structure our joint ventures to be compliant with the provisions of the REIT Investment Diversification and Empowerment Act of 2007 ("RIDEA") which permits NHI to receive rent payments through a triple-net lease between a property company and an operating company and is designed to give NHI the opportunity to capture additional value on the improving performance of the operating company through distributions to a taxable REIT subsidiary ("TRS"). Accordingly, the TRS holds our equity interest in an unconsolidated operating company, which we do not control, and provides an organizational structure that will allow the TRS to engage in a broad range of activities and share in revenues that would otherwise be non-qualifying income under the REIT gross income tests.
Equity-Method Investment	Equity-Method Investment - We report our TRS' investment in an unconsolidated entity, over whose operating and financial policies we have the ability to exercise significant influence but not control, under the equity method of accounting. Under this accounting method, our pro rata share of the entity's earnings or losses is included in our Consolidated Statements of Income. Additionally, we adjust our investment carrying amount to reflect our share of changes in an equity-method investee's capital resulting from its capital transactions. The initial carrying value of our equity-method investment was based on the fair value of the net assets of the entity at the time we acquired our interest. We estimate fair values of the net assets of our equity-method investee based on discounted cash flow models. The inputs we use in these models are based on assumptions that are within a reasonable range of current market rates for the respective investments. We evaluate our equity-method investment for impairment whenever events or changes in circumstances indicate that the carrying value of our investment may exceed the fair value. If it is determined that a decline in the fair value of our investment is not temporary, and if such reduced fair value is below its carrying value, an impairment is recorded. Determining fair value involves significant judgment. Our estimates consider all available evidence including the present value of the expected future cash flows discounted at market rates, general economic conditions and other relevant factors.
Noncontrolling Interest	Noncontrolling Interest - We present the portion of any equity that we do not own in entities that we control (and thus consolidate) as noncontrolling interest and classify such interest as a component of consolidated equity separate from total NHI stockholders' equity in our Consolidated Balance Sheets. In addition, we exclude net income attributable to the noncontrolling interest from net income attributable to common shareholders in our Consolidated Statements of Income.
Use of Estimates	Use of Estimates - The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Earnings Per Share	Earnings Per Share - The weighted average number of common shares outstanding during the reporting period is used to calculate basic earnings per common share. Diluted earnings per common share assume the exercise of stock options using the treasury stock method, to the extent dilutive. Diluted earnings per share also incorporate the potential dilutive impact of our 3.25% convertible senior notes due 2021. We apply the treasury stock method to our convertible debt instruments, the effect of which is that conversion will not be assumed for purposes of computing diluted earnings per share unless the average share price of our common stock for the period exceeds the conversion price per share.
Fair Value Of Financial Instruments	Fair Value Measurements - Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. A three-level fair value hierarchy is required to prioritize the inputs used to measure fair value. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1 - Quoted prices in active markets for identical assets or liabilities. Level 2 - Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs. If the fair value measurement is based on inputs from different levels of the hierarchy, the level within which the entire fair value measurement falls is the lowest level input that is significant to the fair value measurement in its entirety. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. When an event or circumstance alters our assessment of the observability and thus the appropriate classification of an input to a fair value measurement which we deem to be significant to the fair value measurement as a whole, we will transfer that fair value measurement to the appropriate level within the fair value hierarchy.
Property, Plant and Equipment, Impairment	Real Estate Properties - Real estate properties are recorded at cost or, if acquired through business combination, at fair value, including the fair value of contingent consideration, if any. Cost or fair value at the time of acquisition is allocated among land, buildings, tenant improvements, lease and other intangibles, and personal property. For properties acquired in transactions accounted for as asset purchases, the purchase price allocation is based on the relative fair values of the assets acquired. Cost includes the amount of contingent consideration, if any, deemed to be probable of settlement at the acquisition date. Cost also includes capitalized interest during construction periods. We use the straight-line method of depreciation for buildings over their estimated useful lives of 40 years, and improvements over their estimated useful lives ranging from 3 to 25 years. For contingent consideration arising from business combinations, the liability is adjusted to estimated fair value at each reporting date through earnings. For contingent consideration arising from asset acquisitions, the liability is adjusted to the amount considered probable each reporting period, with changes reflected as an adjustment to the basis of the related assets. We evaluate the recoverability of the carrying value of our real estate properties on a property-by-property basis. On a quarterly basis, we review our properties for recoverability when events or circumstances, including significant physical changes in the property, significant adverse changes in general economic conditions and significant deteriorations of the underlying cash flows of the property, indicate that the carrying amount of the property may not be recoverable. The need to recognize an impairment charge is based on estimated undiscounted future cash flows from a property compared to the carrying value of that property. If recognition of an impairment charge is necessary, it is measured as the amount by which the carrying amount of the property exceeds the fair value of the property.
Mortgage Notes Receivable	Mortgage and Other Notes Receivable - Each quarter, we evaluate the carrying values of our notes receivable on an instrument-by-instrument basis for recoverability when events or circumstances, including the non-receipt of contractual principal and interest payments, significant deteriorations of the financial condition of the borrower and significant adverse changes in general economic conditions, indicate that the carrying amount of the note receivable may not be recoverable. If a note receivable becomes more than 30 days delinquent as to contractual principal or interest payments, the loan is classified as non-performing, and thereafter we recognize all amounts due when received. If necessary, an impairment is measured as the amount by which the carrying amount exceeds the discounted cash flows expected to be received under the note receivable or, if foreclosure is probable, the fair value of the collateral securing the note receivable.
Cash and Cash Equivalents	Cash Equivalents - Cash equivalents consist of all highly liquid investments with an original maturity of three months or less.
Concentration Risk, Credit Risk	Concentration of Credit Risks - Our credit risks primarily relate to cash and cash equivalents and investments in mortgage and other notes receivable. Cash and cash equivalents are primarily held in bank accounts and overnight investments. We maintain our bank deposit accounts with large financial institutions in amounts that often exceed federally-insured limits. We have not experienced any losses in such accounts. Our mortgages and other notes receivable consist primarily of secured loans on facilities. Our financial instruments, principally our investments in marketable securities and notes receivable, are subject to the possibility of loss of the carrying values as a result of either the failure of other parties to perform according to their contractual obligations or changes in market prices which may make the instruments less valuable. We obtain collateral in the form of mortgage liens and other protective rights and continually monitor these rights in order to reduce such possibilities of loss. We evaluate the need to provide for reserves for potential losses on our financial instruments based on management's periodic review of our portfolio on an instrument-by-instrument basis.
Marketable Securities	Marketable Securities - Investments in marketable debt and equity securities must be categorized as trading, available-for-sale or held-to-maturity. Our investments in marketable equity securities are classified as available-for-sale securities. Unrealized gains and losses on available-for-sale securities are recorded in other comprehensive income. We evaluate our securities for other-than-temporary impairments on at least a quarterly basis. Realized gains and losses from the sale of available-for-sale securities are determined on a specific-identification basis. A decline in the market value of any available-for-sale or held-to-maturity security below cost that is deemed to be other-than-temporary results in an impairment to reduce the carrying amount to fair value. The impairment is charged to earnings and a new cost basis for the security is established. To determine whether an impairment is other-than-temporary, we consider whether we have the ability and intent to hold the investment until a market price recovery and consider whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for the impairment, the severity and duration of the impairment, changes in value subsequent to year-end and forecasted performance of the investment.
Deferred Charges	Deferred Costs - Costs incurred to acquire debt are amortized by the effective interest method over the term of the related debt.
Revenue Recognition, Deferred Revenue	Deferred Income - Deferred income primarily includes non-refundable loan and lease commitment fees received by us, which are amortized into income over the expected period of the related loan or lease. In the event that our financing commitment to a potential borrower or lessee expires, the related commitment fees are recognized into income immediately. Commitment fees may be charged based on the terms of the loan or lease agreements and the creditworthiness of the parties.
Revenue Recognition	Rental Income - Base rental income is recognized using the straight-line method over the term of the lease to the extent that lease payments are considered collectible. Under certain leases, we receive additional contingent rent, which is calculated on the increase in revenues of the lessee over a base year or base quarter. We recognize contingent rent annually or quarterly when, based on the actual revenues of the lessee, receipt of such income is probable since the target threshold has been achieved. Lease payments that depend on a factor directly related to future use of the property, such as an increase in annual revenues over a base year, are considered to be contingent rentals and are excluded from the schedule of minimum lease payments. If rental income calculated on a straight-line basis exceeds the cash rent due under a lease, the difference is recorded as an increase to straight-line rent receivable in the Consolidated Balance Sheets and an increase in rental income in the Consolidated Statements of Income. If rental income on a straight-line basis is calculated to be less than cash received, there is a decrease in the same accounts. We identify a lease as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to rental income on non-performing leased real estate properties is to recognize rental income in the period when the related cash is received. As of December 31, 2015, we had not identified any of our leases as non-performing. Mortgage Interest Income - Mortgage interest income is recognized based on the interest rates and principal amounts outstanding on the mortgage notes receivable. Under certain mortgages, we receive additional contingent interest, which is calculated on the increase in the current year revenues of a borrower over a base year. We identify a mortgage loan as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to mortgage interest income on non-performing mortgage loans is to recognize mortgage interest income in the period when the cash is received. As of December 31, 2015, we had not identified any of our mortgages as non-performing. Investment Income and Other - Investment income and other includes dividends when declared and interest when earned from our investments in marketable securities, interest on cash and cash equivalents when earned, and amortization of deferred income. Realized gains and losses on sales of marketable securities using the specific-identification method are included as a separate component of continuing operations in the Consolidated Statements of Income as investment and other gains.
Derivatives	Derivatives - In the normal course of business, we are subject to risk from adverse fluctuations in interest rates. We have chosen to manage this risk through the use of derivative financial instruments, primarily interest rate swaps. Counterparties to these contracts are major financial institutions. We are exposed to credit loss in the event of nonperformance by these counterparties. We do not use derivative instruments for trading or speculative purposes. Our objective in managing exposure to market risk is to limit the impact on cash flows. To qualify for hedge accounting, our interest rate swaps must effectively reduce the risk exposure that they are designed to hedge. In addition, at inception of a qualifying cash flow hedging relationship, the underlying transaction or transactions must be, and be expected to remain, probable of occurring in accordance with our related assertions. All of our hedges are cash flow hedges. We recognize all derivative instruments, including embedded derivatives required to be bifurcated, as assets or liabilities at their fair value in the Consolidated Balance Sheets. Changes in the fair value of derivative instruments that are not designated as hedges or that do not meet the criteria of hedge accounting are recognized in earnings. For derivatives designated in qualifying cash flow hedging relationships, the change in fair value of the effective portion of the derivatives is recognized in accumulated other comprehensive income (loss), whereas the change in fair value of the ineffective portion is recognized in earnings. Gains and losses are reclassified from accumulated other comprehensive income into earnings once the underlying hedged transaction is recognized in earnings.
Income Tax	Federal Income Taxes - We intend at all times to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. We record income tax expense or benefit with respect to one of our subsidiaries which is taxed as a Taxable REIT Subsidiary ("TRS") under provisions similar to those applicable to regular corporations. Aside from such income taxes which may be applicable to the taxable income in the TRS, we will not be subject to U.S. federal income tax, provided that we continue to qualify as a REIT and make distributions to stockholders at least equal to or in excess of 90% our taxable income. Accordingly, no provision for federal income taxes has been made in the consolidated financial statements, except for the provision on the taxable income of the TRS, which is included in our consolidated statements of income under the caption, "Income tax benefit (expense) of taxable REIT subsidiary." Our failure to continue to qualify under the applicable REIT qualification rules and regulations would have a material adverse impact on our financial position, results of operations and cash flows. Earnings and profits, which determine the taxability of dividends to stockholders, differ from net income reported for financial reporting purposes due primarily to differences in the basis of assets, estimated useful lives used to compute depreciation expense, gains on sales of real estate, non-cash compensation expense and recognition of commitment fees. Our tax returns filed for years beginning in 2012 are subject to examination by taxing authorities. We classify interest and penalties related to uncertain tax positions, if any, in our consolidated financial statements as a component of income tax expense.
Segment Reporting	Segment Disclosures - We are in the business of owning and financing health care properties. We are managed as one segment, rather than multiple segments for internal purposes and for internal decision making.
Reclassification, Policy [Policy Text Block]	Reclassifications - The results of operations for facilities sold, including the gain or loss on such sales, prior to the adoption of ASU 2014-08 have been reported for 2013 and prior periods as discontinued operations in the Consolidated Statements of Income. For all periods presented, we have reclassified the income tax benefit (expense) related to our taxable REIT subsidiary as a separate line item in our Consolidated Statements of Income.
New Accounting Pronouncements	New Accounting Pronouncements - In the first quarter of 2014, we adopted ASU 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. Under ASU 2014-08, disposals will be reported as discontinued operations only when the disposal represents a strategic shift that will have a major effect on our operations and financial results. Previously, we reported the disposition of components that were either reporting units, subsidiaries, or asset groups as discontinued operations. ASU 2014-08 is effective for all disposals (or classifications as held for sale) of components that occur on or after December 15, 2014. We have elected early adoption, under which terms we will prospectively apply ASU 2014-08 and report as discontinued operations only those disposals (or classifications as held for sale) that have not been previously reported. Accordingly, we have continued to report the 2013 operations of facilities meeting the accounting criteria for either being sold or held for sale as discontinued operations in the Consolidated Statements of Income. In May 2014 the Financial Accounting Standards Board (“FASB”) issued ASU 2014-09, Revenue from Contracts with Customers. ASU 2014-09 provides a principles-based approach for a broad range of revenue generating transactions, including the sale of real estate, which will generally require more estimates and more judgment and more disclosures than under current guidance. Because this ASU specifically excludes lease contracts from its scope, its application is not expected to impact our recognition of rental income on a straight-line basis. In August 2015 the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09, Revenue from Contracts with Customers. ASU 2014-09 is now effective for public entities for annual periods beginning after December 15, 2017, including interim periods therein. Early adoption is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The adoption of ASU 2014-09 is not expected to have a material effect on our consolidated financial statements. In February 2015 the FASB issued ASU 2015-16, Amendments to the Consolidation Analysis, under ASU 2015-02, which is generally effective for fiscal years and interim periods beginning after December 15, 2015. ASU 2015-02 changes the consolidation analysis for all reporting entities. The changes primarily affect the consolidation of limited partnerships and their equivalents (e.g., limited liability corporations), the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships, as well as structured vehicles such as collateralized debt obligations. The adoption of ASU 2015-16 is not expected to have a material effect on our consolidated financial statements. In April 2015 the FASB issued ASU 2015-03, Interest-Imputation of Interest, whose primary effect is to mandate that debt issuance costs be reported in the balance sheet as a direct deduction from the face amount of the related liability. Debt issuance costs have previously been presented among assets on the balance sheet. The standard does not affect the recognition and measurement of debt issuance costs. The ASU is effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted. In August 2015 the FASB issued ASU 2015-15, Interest-Imputation of Interest (Subtopic 835-30) Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting. The ASU clarifies the treatment of debt issuance costs related to revolving credit facilities, upon which ASU 2015-03 was silent. ASU 2015-15 notes that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. We believe our eventual adoption of these standards on the imputation of interest will have no material effect on our reported financial position and results of operations. At its November 11, 2015, meeting, the FASB agreed on the effective date of the May 2013 Exposure Draft Leases - Joint Project of the FASB and the IASB (the "Standard"), which is in continuing deliberation by the board. Public companies will be required to apply the Standard for all accounting periods beginning after December 15, 2018 - for REITs this means application will be required beginning Jan. 1, 2019. The FASB decided to permit early adoption upon the issuance of the Standard and plans to issue the Standard in early 2016. All leases with lease terms greater than one year will be subject to the Standard, including leases in place as of the adoption date. Management expects that, because of the Standard’s emphasis on lessee accounting, the Standard will have little impact on its accounting for leases. Consistent with present standards, NHI will continue to account for lease revenue on a straight-line basis for most leases. Also consistent with NHI’s current practice, under the Standard only initial direct costs that are incremental to the lessor will be capitalized.

Significant Accounting Policies (Policy)

12 Months Ended

Dec. 31, 2015

Business Description and Basis of Presentation

The Company - National Health Investors, Inc. ("NHI" or the "Company"), a Maryland corporation incorporated and publicly listed in 1991, is a real estate investment trust (“REIT”) specializing in sale-leaseback, joint-venture, mortgage and mezzanine financing of need-driven and discretionary senior housing and medical investments. Our portfolio consists of real estate investments in independent, assisted and memory care communities, entrance-fee communities, senior living campuses, skilled nursing facilities, specialty hospitals and medical office buildings. Other investments include mortgages and notes, marketable securities, including the common shares of other publicly-held REITs, and a joint venture structured to comply with the provisions of the REIT Investment Diversification Empowerment Act of 2007 (“RIDEA”). Through this RIDEA joint venture, we invest in facility operations, managed by independent third-parties. We fund our real estate investments primarily through: (1) operating cash flow, (2) debt offerings, including bank lines of credit and ordinary term debt, and (3) the sale of equity securities.

Consolidation

Principles of Consolidation - The accompanying consolidated financial statements include our accounts and the accounts of our wholly-owned subsidiaries, joint ventures, partnerships and consolidated variable interest entities ("VIE") where NHI controls the operating activities of the VIE, if any. All intercompany transactions and balances have been eliminated in consolidation. Net income is reduced by the portion of net income attributable to noncontrolling interests.

A VIE is broadly defined as an entity with one or more of the following characteristics: (a) the total equity investment at risk is insufficient to finance the entity's activities without additional subordinated financial support; (b) as a group, the holders of the equity investment at risk lack (i) the ability to make decisions about the entity's activities through voting or similar rights, (ii) the obligation to absorb the expected losses of the entity, or (iii) the right to receive the expected residual returns of the entity; or (c) the equity investors have voting rights that are not proportional to their economic interests, and substantially all of the entity's activities either involve, or are conducted on behalf of, an investor that has disproportionately few voting rights.

We apply Financial Accounting Standards Board ("FASB") guidance for our arrangements with variable interest entities ("VIEs") which requires us to identify entities for which control is achieved through means other than voting rights and to determine which business enterprise is the primary beneficiary of the VIE. In accordance with FASB guidance, management must evaluate each of the Company’s contractual relationships which creates a variable interest in other entities. If the Company has a variable interest and the entity is a VIE, then management must determine whether or not the Company is the primary beneficiary of the VIE. If it is determined that the Company is the primary beneficiary, NHI consolidates the VIE. We identify the primary beneficiary of a VIE as the enterprise that has both: (i) the power to direct the activities of the VIE that most significantly impact the entity's economic performance; and (ii) the obligation to absorb losses or the right to receive benefits of the VIE that could be significant to the entity. We perform this analysis on an ongoing basis.

At December 31, 2015, we held an interest in four unconsolidated VIEs, consisting of 1) a start-up lessee in which NHI's variable interest consists of its leasehold interest, analogous to a financing arrangement, and of which we concluded that NHI was not the primary beneficiary (Note 2); 2) our joint venture in an operating company organized under provisions of the REIT Investment Diversification and Empowerment Act, (“RIDEA”) of which we concluded that NHI was not the primary beneficiary (Note 3); 3) a note receivable from, a guarantee on a letter of credit for, and a purchase option with, an unconsolidated VIE of whom we concluded that NHI was not the primary beneficiary (Note 4); and 4) two construction mortgage notes receivable aggregating $83,411,000 from an unconsolidated VIE of whom we concluded that NHI was not the primary beneficiary (Note 4). Our direct support of the above VIEs has been limited to the transactions described herein, including our commitments and contingencies described in Note 8, and any decision to furnish additional direct support would be at our discretion and not obligatory. We believe our exposure to loss as a result of our involvement with these unconsolidated VIEs would be limited to our carrying value of these investments and the amount of our commitment as guarantor under the letter of credit. Generally, we lack, either directly or through related parties, any material input in the activities that most significantly impact the economic performance of these entities.

We apply FASB guidance related to investments in joint ventures based on the type of controlling rights held by the members' interests in limited liability companies that may preclude consolidation by the majority equity owner in certain circumstances in which the majority equity owner would otherwise consolidate the joint venture.

We structure our joint ventures to be compliant with the provisions of the REIT Investment Diversification and Empowerment Act of 2007 ("RIDEA") which permits NHI to receive rent payments through a triple-net lease between a property company and an operating company and is designed to give NHI the opportunity to capture additional value on the improving performance of the operating company through distributions to a taxable REIT subsidiary ("TRS"). Accordingly, the TRS holds our equity interest in an unconsolidated operating company, which we do not control, and provides an organizational structure that will allow the TRS to engage in a broad range of activities and share in revenues that would otherwise be non-qualifying income under the REIT gross income tests.

Equity-Method Investment

Equity-Method Investment - We report our TRS' investment in an unconsolidated entity, over whose operating and financial policies we have the ability to exercise significant influence but not control, under the equity method of accounting. Under this accounting method, our pro rata share of the entity's earnings or losses is included in our Consolidated Statements of Income. Additionally, we adjust our investment carrying amount to reflect our share of changes in an equity-method investee's capital resulting from its capital transactions.

The initial carrying value of our equity-method investment was based on the fair value of the net assets of the entity at the time we acquired our interest. We estimate fair values of the net assets of our equity-method investee based on discounted cash flow models. The inputs we use in these models are based on assumptions that are within a reasonable range of current market rates for the respective investments.

We evaluate our equity-method investment for impairment whenever events or changes in circumstances indicate that the carrying value of our investment may exceed the fair value. If it is determined that a decline in the fair value of our investment is not temporary, and if such reduced fair value is below its carrying value, an impairment is recorded. Determining fair value involves significant judgment. Our estimates consider all available evidence including the present value of the expected future cash flows discounted at market rates, general economic conditions and other relevant factors.

Noncontrolling Interest

Noncontrolling Interest - We present the portion of any equity that we do not own in entities that we control (and thus consolidate) as noncontrolling interest and classify such interest as a component of consolidated equity separate from total NHI stockholders' equity in our Consolidated Balance Sheets. In addition, we exclude net income attributable to the noncontrolling interest from net income attributable to common shareholders in our Consolidated Statements of Income.

Use of Estimates

Use of Estimates - The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Earnings Per Share

Earnings Per Share - The weighted average number of common shares outstanding during the reporting period is used to calculate basic earnings per common share. Diluted earnings per common share assume the exercise of stock options using the treasury stock method, to the extent dilutive. Diluted earnings per share also incorporate the potential dilutive impact of our 3.25% convertible senior notes due 2021. We apply the treasury stock method to our convertible debt instruments, the effect of which is that conversion will not be assumed for purposes of computing diluted earnings per share unless the average share price of our common stock for the period exceeds the conversion price per share.

Fair Value Of Financial Instruments

Fair Value Measurements - Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. A three-level fair value hierarchy is required to prioritize the inputs used to measure fair value. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs.

The three levels of inputs used to measure fair value are as follows:

Level 1 - Quoted prices in active markets for identical assets or liabilities.

Level 2 - Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data.

Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.

If the fair value measurement is based on inputs from different levels of the hierarchy, the level within which the entire fair value measurement falls is the lowest level input that is significant to the fair value measurement in its entirety. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. When an event or circumstance alters our assessment of the observability and thus the appropriate classification of an input to a fair value measurement which we deem to be significant to the fair value measurement as a whole, we will transfer that fair value measurement to the appropriate level within the fair value hierarchy.

Property, Plant and Equipment, Impairment

Real Estate Properties - Real estate properties are recorded at cost or, if acquired through business combination, at fair value, including the fair value of contingent consideration, if any. Cost or fair value at the time of acquisition is allocated among land, buildings, tenant improvements, lease and other intangibles, and personal property. For properties acquired in transactions accounted for as asset purchases, the purchase price allocation is based on the relative fair values of the assets acquired. Cost includes the amount of contingent consideration, if any, deemed to be probable of settlement at the acquisition date. Cost also includes capitalized interest during construction periods. We use the straight-line method of depreciation for buildings over their estimated useful lives of 40 years, and improvements over their estimated useful lives ranging from 3 to 25 years. For contingent consideration arising from business combinations, the liability is adjusted to estimated fair value at each reporting date through earnings. For contingent consideration arising from asset acquisitions, the liability is adjusted to the amount considered probable each reporting period, with changes reflected as an adjustment to the basis of the related assets.

We evaluate the recoverability of the carrying value of our real estate properties on a property-by-property basis. On a quarterly basis, we review our properties for recoverability when events or circumstances, including significant physical changes in the property, significant adverse changes in general economic conditions and significant deteriorations of the underlying cash flows of the property, indicate that the carrying amount of the property may not be recoverable. The need to recognize an impairment charge is based on estimated undiscounted future cash flows from a property compared to the carrying value of that property. If recognition of an impairment charge is necessary, it is measured as the amount by which the carrying amount of the property exceeds the fair value of the property.

Mortgage Notes Receivable

Mortgage and Other Notes Receivable - Each quarter, we evaluate the carrying values of our notes receivable on an instrument-by-instrument basis for recoverability when events or circumstances, including the non-receipt of contractual principal and interest payments, significant deteriorations of the financial condition of the borrower and significant adverse changes in general economic conditions, indicate that the carrying amount of the note receivable may not be recoverable. If a note receivable becomes more than 30 days delinquent as to contractual principal or interest payments, the loan is classified as non-performing, and thereafter we recognize all amounts due when received. If necessary, an impairment is measured as the amount by which the carrying amount exceeds the discounted cash flows expected to be received under the note receivable or, if foreclosure is probable, the fair value of the collateral securing the note receivable.

Cash and Cash Equivalents

Cash Equivalents - Cash equivalents consist of all highly liquid investments with an original maturity of three months or less.

Concentration Risk, Credit Risk

Concentration of Credit Risks - Our credit risks primarily relate to cash and cash equivalents and investments in mortgage and other notes receivable. Cash and cash equivalents are primarily held in bank accounts and overnight investments. We maintain our bank deposit accounts with large financial institutions in amounts that often exceed federally-insured limits. We have not experienced any losses in such accounts. Our mortgages and other notes receivable consist primarily of secured loans on facilities.

Our financial instruments, principally our investments in marketable securities and notes receivable, are subject to the possibility of loss of the carrying values as a result of either the failure of other parties to perform according to their contractual obligations or changes in market prices which may make the instruments less valuable. We obtain collateral in the form of mortgage liens and other protective rights and continually monitor these rights in order to reduce such possibilities of loss. We evaluate the need to provide for reserves for potential losses on our financial instruments based on management's periodic review of our portfolio on an instrument-by-instrument basis.

Marketable Securities

Marketable Securities - Investments in marketable debt and equity securities must be categorized as trading, available-for-sale or held-to-maturity. Our investments in marketable equity securities are classified as available-for-sale securities. Unrealized gains and losses on available-for-sale securities are recorded in other comprehensive income. We evaluate our securities for other-than-temporary impairments on at least a quarterly basis. Realized gains and losses from the sale of available-for-sale securities are determined on a specific-identification basis.

A decline in the market value of any available-for-sale or held-to-maturity security below cost that is deemed to be other-than-temporary results in an impairment to reduce the carrying amount to fair value. The impairment is charged to earnings and a new cost basis for the security is established. To determine whether an impairment is other-than-temporary, we consider whether we have the ability and intent to hold the investment until a market price recovery and consider whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for the impairment, the severity and duration of the impairment, changes in value subsequent to year-end and forecasted performance of the investment.

Deferred Charges

Deferred Costs - Costs incurred to acquire debt are amortized by the effective interest method over the term of the related debt.

Revenue Recognition, Deferred Revenue

Deferred Income - Deferred income primarily includes non-refundable loan and lease commitment fees received by us, which are amortized into income over the expected period of the related loan or lease. In the event that our financing commitment to a potential borrower or lessee expires, the related commitment fees are recognized into income immediately. Commitment fees may be charged based on the terms of the loan or lease agreements and the creditworthiness of the parties.

Revenue Recognition

Rental Income - Base rental income is recognized using the straight-line method over the term of the lease to the extent that lease payments are considered collectible. Under certain leases, we receive additional contingent rent, which is calculated on the increase in revenues of the lessee over a base year or base quarter. We recognize contingent rent annually or quarterly when, based on the actual revenues of the lessee, receipt of such income is probable since the target threshold has been achieved. Lease payments that depend on a factor directly related to future use of the property, such as an increase in annual revenues over a base year, are considered to be contingent rentals and are excluded from the schedule of minimum lease payments.

If rental income calculated on a straight-line basis exceeds the cash rent due under a lease, the difference is recorded as an increase to straight-line rent receivable in the Consolidated Balance Sheets and an increase in rental income in the Consolidated Statements of Income. If rental income on a straight-line basis is calculated to be less than cash received, there is a decrease in the same accounts.

We identify a lease as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to rental income on non-performing leased real estate properties is to recognize rental income in the period when the related cash is received. As of December 31, 2015, we had not identified any of our leases as non-performing.

Mortgage Interest Income - Mortgage interest income is recognized based on the interest rates and principal amounts outstanding on the mortgage notes receivable. Under certain mortgages, we receive additional contingent interest, which is calculated on the increase in the current year revenues of a borrower over a base year. We identify a mortgage loan as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to mortgage interest income on non-performing mortgage loans is to recognize mortgage interest income in the period when the cash is received. As of December 31, 2015, we had not identified any of our mortgages as non-performing.

Investment Income and Other - Investment income and other includes dividends when declared and interest when earned from our investments in marketable securities, interest on cash and cash equivalents when earned, and amortization of deferred income. Realized gains and losses on sales of marketable securities using the specific-identification method are included as a separate component of continuing operations in the Consolidated Statements of Income as investment and other gains.

Derivatives

Derivatives - In the normal course of business, we are subject to risk from adverse fluctuations in interest rates. We have chosen to manage this risk through the use of derivative financial instruments, primarily interest rate swaps. Counterparties to these contracts are major financial institutions. We are exposed to credit loss in the event of nonperformance by these counterparties. We do not use derivative instruments for trading or speculative purposes. Our objective in managing exposure to market risk is to limit the impact on cash flows.

To qualify for hedge accounting, our interest rate swaps must effectively reduce the risk exposure that they are designed to hedge. In addition, at inception of a qualifying cash flow hedging relationship, the underlying transaction or transactions must be, and be expected to remain, probable of occurring in accordance with our related assertions. All of our hedges are cash flow hedges.

We recognize all derivative instruments, including embedded derivatives required to be bifurcated, as assets or liabilities at their fair value in the Consolidated Balance Sheets. Changes in the fair value of derivative instruments that are not designated as hedges or that do not meet the criteria of hedge accounting are recognized in earnings. For derivatives designated in qualifying cash flow hedging relationships, the change in fair value of the effective portion of the derivatives is recognized in accumulated other comprehensive income (loss), whereas the change in fair value of the ineffective portion is recognized in earnings. Gains and losses are reclassified from accumulated other comprehensive income into earnings once the underlying hedged transaction is recognized in earnings.

Income Tax

Federal Income Taxes - We intend at all times to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. We record income tax expense or benefit with respect to one of our subsidiaries which is taxed as a Taxable REIT Subsidiary ("TRS") under provisions similar to those applicable to regular corporations. Aside from such income taxes which may be applicable to the taxable income in the TRS, we will not be subject to U.S. federal income tax, provided that we continue to qualify as a REIT and make distributions to stockholders at least equal to or in excess of 90% our taxable income. Accordingly, no provision for federal income taxes has been made in the consolidated financial statements, except for the provision on the taxable income of the TRS, which is included in our consolidated statements of income under the caption, "Income tax benefit (expense) of taxable REIT subsidiary." Our failure to continue to qualify under the applicable REIT qualification rules and regulations would have a material adverse impact on our financial position, results of operations and cash flows.

Earnings and profits, which determine the taxability of dividends to stockholders, differ from net income reported for financial reporting purposes due primarily to differences in the basis of assets, estimated useful lives used to compute depreciation expense, gains on sales of real estate, non-cash compensation expense and recognition of commitment fees.

Our tax returns filed for years beginning in 2012 are subject to examination by taxing authorities. We classify interest and penalties related to uncertain tax positions, if any, in our consolidated financial statements as a component of income tax expense.

Segment Reporting

Segment Disclosures - We are in the business of owning and financing health care properties. We are managed as one segment, rather than multiple segments for internal purposes and for internal decision making.

Reclassification, Policy [Policy Text Block]

Reclassifications - The results of operations for facilities sold, including the gain or loss on such sales, prior to the adoption of ASU 2014-08 have been reported for 2013 and prior periods as discontinued operations in the Consolidated Statements of Income. For all periods presented, we have reclassified the income tax benefit (expense) related to our taxable REIT subsidiary as a separate line item in our Consolidated Statements of Income.

New Accounting Pronouncements

New Accounting Pronouncements - In the first quarter of 2014, we adopted ASU 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. Under ASU 2014-08, disposals will be reported as discontinued operations only when the disposal represents a strategic shift that will have a major effect on our operations and financial results. Previously, we reported the disposition of components that were either reporting units, subsidiaries, or asset groups as discontinued operations. ASU 2014-08 is effective for all disposals (or classifications as held for sale) of components that occur on or after December 15, 2014. We have elected early adoption, under which terms we will prospectively apply ASU 2014-08 and report as discontinued operations only those disposals (or classifications as held for sale) that have not been previously reported. Accordingly, we have continued to report the 2013 operations of facilities meeting the accounting criteria for either being sold or held for sale as discontinued operations in the Consolidated Statements of Income.

In May 2014 the Financial Accounting Standards Board (“FASB”) issued ASU 2014-09, Revenue from Contracts with Customers. ASU 2014-09 provides a principles-based approach for a broad range of revenue generating transactions, including the sale of real estate, which will generally require more estimates and more judgment and more disclosures than under current guidance. Because this ASU specifically excludes lease contracts from its scope, its application is not expected to impact our recognition of rental income on a straight-line basis. In August 2015 the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09, Revenue from Contracts with Customers. ASU 2014-09 is now effective for public entities for annual periods beginning after December 15, 2017, including interim periods therein. Early adoption is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The adoption of ASU 2014-09 is not expected to have a material effect on our consolidated financial statements.

In February 2015 the FASB issued ASU 2015-16, Amendments to the Consolidation Analysis, under ASU 2015-02, which is generally effective for fiscal years and interim periods beginning after December 15, 2015. ASU 2015-02 changes the consolidation analysis for all reporting entities. The changes primarily affect the consolidation of limited partnerships and their equivalents (e.g., limited liability corporations), the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships, as well as structured vehicles such as collateralized debt obligations. The adoption of ASU 2015-16 is not expected to have a material effect on our consolidated financial statements.

In April 2015 the FASB issued ASU 2015-03, Interest-Imputation of Interest, whose primary effect is to mandate that debt issuance costs be reported in the balance sheet as a direct deduction from the face amount of the related liability. Debt issuance costs have previously been presented among assets on the balance sheet. The standard does not affect the recognition and measurement of debt issuance costs. The ASU is effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted. In August 2015 the FASB issued ASU 2015-15, Interest-Imputation of Interest (Subtopic 835-30) Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting. The ASU clarifies the treatment of debt issuance costs related to revolving credit facilities, upon which ASU 2015-03 was silent. ASU 2015-15 notes that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. We believe our eventual adoption of these standards on the imputation of interest will have no material effect on our reported financial position and results of operations.

At its November 11, 2015, meeting, the FASB agreed on the effective date of the May 2013 Exposure Draft Leases - Joint Project of the FASB and the IASB (the "Standard"), which is in continuing deliberation by the board. Public companies will be required to apply the Standard for all accounting periods beginning after December 15, 2018 - for REITs this means application will be required beginning Jan. 1, 2019. The FASB decided to permit early adoption upon the issuance of the Standard and plans to issue the Standard in early 2016. All leases with lease terms greater than one year will be subject to the Standard, including leases in place as of the adoption date. Management expects that, because of the Standard’s emphasis on lessee accounting, the Standard will have little impact on its accounting for leases. Consistent with present standards, NHI will continue to account for lease revenue on a straight-line basis for most leases. Also consistent with NHI’s current practice, under the Standard only initial direct costs that are incremental to the lessor will be capitalized.