This element represents the number of buildings acquired or agreed to be acquired by the entity during the period.

No definition available.

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Represents the number of communities.

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This element represents the number of properties acquired or agreed to be acquired by the entity during the period.

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No definition available.

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This element represents the number of properties sold or agreed to be sold by the entity.

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No definition available.

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- Definition

The pro forma net income or loss for the period as if the significant acquisitions or disposals had been completed at the beginning of the period.

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No definition available.

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The pro forma basic net income per share for a period as if the significant acquisitions or disposals had been completed at the beginning of the period.

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No definition available.

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The pro forma revenue for a period as if the significant acquisitions or disposals had been completed at the beginning of the period.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Weighted average interest rate of debt outstanding.

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No definition available.

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The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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No definition available.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the additional capital contribution to the entity.

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Number of new stock issued during the period.

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Pro Forma Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended		3 Months Ended			12 Months Ended	1 Months Ended		4 Months Ended
	Feb. 28, 2015 property	Apr. 30, 2014	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2014 community	Jan. 31, 2015 property building	May 31, 2014	Sep. 30, 2014
Pro Forma Information
Number of properties to be sold	1snh_NumberOfPropertiesSold
Interest rate (as a percent)			1.57%
Mortgage debt assumed			$ 29,955
Common shares issued in public offering	31,050,000	15,525,000		31,050,000
Net proceeds from issuance of common shares issued in public offering	659,750	322,807	659,750	659,750
Pro Forma
Pro forma results of operations
Total revenues			254,851		254,301
Net income			45,628		36,065
Per common share data:
Net income per share(in dollars per share)			$ 0.19		$ 0.15
Senior living communities
Pro Forma Information
Number of communities						5
Acquisition
Pro Forma Information
Number of properties acquired or agreed to be acquired			23
Aggregate purchase price properties, excluding closing costs			539,000
Mortgage debt assumed			29,955
Weighted average interest rate on debt (as a percent)			4.73%
Property operating expenses			1,094
Total rental income recognized			7,046
Acquisition \| Senior living communities
Pro Forma Information
Number of properties acquired or agreed to be acquired						2
Acquisition \| Senior living communities \| Pro Forma
Pro Forma Information
Number of communities			37		37
Acquisition \| MOBs
Pro Forma Information
Number of properties acquired or agreed to be acquired			23			2	23
Number of buildings acquired						3	23
Aggregate purchase price properties, excluding closing costs						1,204,393
Mortgage debt assumed			(29,955)			15,630	(29,955)
Weighted average interest rate on debt (as a percent)						6.28%
Senior unsecured notes 3.25%
Pro Forma Information
Interest rate (as a percent)		3.25%
Principal amount of debt		400,000
Senior unsecured notes 4.75%
Pro Forma Information
Interest rate (as a percent)		4.75%
Principal amount of debt		250,000
Unsecured Debt
Pro Forma Information
Weighted average interest rate on debt (as a percent)				1.59%
Principal amount of debt			$ 350,000	$ 350,000				$ 350,000
Interest rate, description								LIBOR	LIBOR
Interest rate added to the base rate (as a percent)								1.40%