Organization, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Segments	Segments At March 31, 2018, the Company had three reportable operating segments: Core Portfolio, Funds and Structured Financing. The Company’s chief operating decision maker may review operational and financial data on a property basis and does not differentiate properties on a geographical basis for purposes of allocating resources or capital. Each property is considered a separate operating segment; however, each property on a stand-alone basis represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the consolidated accounts of the Company and its investments in partnerships and limited liability companies in which the Company has control in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 810 “Consolidation” (“ASC Topic 810”). The ownership interests of other investors in these entities are recorded as noncontrolling interests. All significant intercompany balances and transactions have been eliminated in consolidation. Investments in entities for which the Company has the ability to exercise significant influence over, but does not have financial or operating control, are accounted for using the equity method of accounting. Accordingly, the Company’s share of the earnings (or losses) of these entities are included in consolidated net income. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. Operating results for the interim periods presented are not necessarily indicative of the results that may be expected for the full fiscal year. The information furnished in the accompanying consolidated financial statements reflects all adjustments that, in the opinion of management, are necessary for a fair presentation of the aforementioned consolidated financial statements for the interim periods. Such adjustments consisted of normal recurring items. These consolidated financial statements should be read in conjunction with the Company’s 2017 Annual Report on Form 10-K, as filed with the SEC on February 27, 2018.
Use of Estimates	Use of Estimates GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The most significant assumptions and estimates relate to the valuation of real estate, depreciable lives, revenue recognition and the collectability of notes receivable and rents receivable. Application of these estimates and assumptions requires the exercise of judgment as to future uncertainties and, as a result, actual results could differ from these estimates.
Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers. ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. ASU 2014-09 does not apply to the Company’s lease revenues, but will apply to reimbursed tenant costs. Additionally, this guidance modifies disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year, until years beginning in 2018, with early adoption permitted but not before 2017. Entities may adopt ASU 2014-09 using either a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients or a modified retrospective approach with the cumulative effect, recognized at the date of adoption. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. The Company implemented the standard using the modified retrospective approach; however, there was no cumulative effect required to be recognized in retained earnings at the date of application. With respect to its fee-derived revenue, the Company had no changes to the timing of the Company’s revenue recognition. However, the recognition of gains on sales of properties may be impacted prospectively under limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 provides guidance on certain specific cash flow issues, including, but not limited to, debt prepayment or extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees. ASU 2016-15 is effective for periods beginning after December 15, 2017, with early adoption permitted and shall be applied retrospectively where practicable. The Company adopted ASU 2016-15 effective January 1, 2018 and elected the “cumulative distribution approach” whereby distributions received from equity method investments would be classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Upon the adoption, the Company reclassified $7.3 million of its cash inflows from investing activities to cash flows from operating activities in its historical presentation of cash flows related to its equity method investments for the three months ended March 31, 2017. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. ASU 2016-18 requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for public business entities in fiscal years beginning after December 15, 2017, with early adoption permitted. The Company adopted this guidance effective January 1, 2018. Upon the adoption, the Company reclassified $1.0 million of its cash inflows from operating activities to change in cash and restricted cash in its historical presentation of cash flows for the three months ended March 31, 2017. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations – Clarifying the Definition of a Business. ASU 2017-01 clarifies that to be considered a business, the elements must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output. The new standard illustrates the circumstances under which real estate with in-place leases would be considered a business and provides guidance for the identification of assets and liabilities in purchase accounting. ASU 2017-01 is effective for periods beginning after December 15, 2017 and has been adopted by the Company effective January 1, 2018. It is expected that the new standard will reduce the number of future real estate acquisitions that will be accounted for as business combinations and, therefore, reduce the amount of acquisition costs that will be expensed. Accordingly, the Company capitalized $0.1 million of acquisition costs during the three months ended March 31, 2018 and expensed $0.3 million of acquisition costs during the three months ended March 31, 2017. In January 2017, the FASB issued ASU No. 2017-03, Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323). ASU 2017-03 amends certain SEC guidance in the FASB Accounting Standards Codification in response to SEC staff announcements made during 2016 Emerging Issues Task Force (“EITF”) meetings which addressed (i) the additional qualitative disclosures that a registrant is expected to provide when it cannot reasonably estimate the impact that ASUs 2014-09, 2016-02 and 2016-13 will have in applying the guidance in Staff Accounting Bulletin Topic 11.M and (ii) guidance in ASC 323 related to the amendments made by ASU 2014-01 regarding use of the proportional amortization method in accounting for investments in qualified affordable housing projects (announcement made at the November 17, 2016, EITF meeting). The Company adopted 2017-03 effective January 1, 2018. The adoption of ASU 2017-03 did not have a material impact on the Company’s consolidated financial statements. In February 2017, the FASB issued ASU 2017-05, Other Income—Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets, which amends the guidance on nonfinancial assets in ASC 610-20. The amendments clarify that (i) a financial asset is within the scope of ASC 610-20 if it meets the definition of an in substance nonfinancial asset and may include nonfinancial assets transferred within a legal entity to a counter-party, (ii) an entity should identify each distinct nonfinancial asset or in substance nonfinancial asset promised to a counter-party and de-recognize each asset when a counter-party obtains control of it, and (iii) an entity should allocate consideration to each distinct asset by applying the guidance in ASC 606 on allocating the transaction price to performance obligations. Further, ASU 2017-05 provides guidance on accounting for partial sales of nonfinancial assets. The amendments are effective at the same time as the amendments in ASU 2014-09. The Company adopted ASU 2017-05 effective January 1, 2018. The adoption of ASU 2017-05 did not have a material impact on the Company's consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting, which clarifies the scope of modification accounting with respect to changes to the terms or conditions of a share-based payment award. Modification accounting would not apply if a change to an award does not affect the total current fair value (or other applicable measurement), vesting conditions, or the classification of the award. For all entities, ASU 2017-09 is effective prospectively for awards modified in fiscal years beginning after December 15, 2017. The Company adopted ASU 2017-09 effective January 1, 2018. The adoption of ASU 2017-09 did not have a material impact on the Company's consolidated financial statements because the Company has not had significant modifications of its awards. In August 2017, the Financial Accounting Standards Board issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. The Company early adopted ASU 2017-12 effective January 1, 2018 and the adoption of ASU 2017-12 did not have a material impact on the Company's consolidated financial statements. In March 2018, the FASB issued ASU 2018-05, Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, which allowed public companies to record provisional amounts in earnings for the year ended December 31, 2017 due to the complexities involved in accounting for the enactment of the Tax Cuts and Jobs Act. ASU 2018-05 was effective upon issuance. The Company recognized the estimated income tax effects of the Tax Cuts and Jobs Act in its 2017 Consolidated Financial Statements in accordance with SEC Staff Accounting Bulletin No. 118. Recently Issued Accounting Pronouncements In February 2018, the FASB issued ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. These amendments provide financial statement preparers with an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Cuts and Jobs Act is recorded. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods therein. Early adoption is permitted. We are currently assessing the impact this guidance will have on our consolidated financial statements.