Schedule III Real Estate and Accumulated Depreciation (Parenthetical) (Details)	12 Months Ended
	Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015	Sep. 30, 2016 USD ($)
Real Estate and Accumulated Depreciation [Line Items]
SEC Schedule III, Real Estate, Federal Income Tax Basis	$ 10,450,000,000
Finite-Lived Intangible Assets, Remaining Amortization Period	6 months
Encumbrance 1 | FNMA
Real Estate and Accumulated Depreciation [Line Items]
Secured credit facilities, amount available	$ 160,000,000
Line of credit facility, amount outstanding	$ 160,000,000
Variable interest rate (percent)	1.10%
Encumbrance 1 | FNMA | Interest Rate Swap
Real Estate and Accumulated Depreciation [Line Items]
Number of Interest rate derivatives held (contracts) | Contract	2
Variable rate borrowings after interest rate swaps (percent)	4.50%
Encumbrance 1 | FNMA | Interest Rate Cap
Real Estate and Accumulated Depreciation [Line Items]
Derivative, Notional Amount	$ 50,000,000
Encumbrance 2 | Fixed Rate Debt | Loan [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of bond used as encumbrance	$ 127,000,000
Derivative, Notional Amount			$ 128,000,000
Derivative cap interest rate (percent)	4.50%
Derivative termination date	Jun. 10, 2021
Furniture, fixtures and equipment
Real Estate and Accumulated Depreciation [Line Items]
Estimated useful lives (years)	5 years
Minimum | Land improvements and buildings
Real Estate and Accumulated Depreciation [Line Items]
Estimated useful lives (years)	8 years
Maximum | Land improvements and buildings
Real Estate and Accumulated Depreciation [Line Items]
Estimated useful lives (years)	40 years
Corporate Real Estate Owned | Minimum
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Life Used for Depreciation		1 year
Corporate Real Estate Owned | Maximum
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Life Used for Depreciation		40 years