SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION - Footnotes (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Real Estate And Accumulated Depreciation
Fair value adjustment, liabilities	$ 1,906
Aggregate cost for federal income tax purposes	8,700,000
Capital leases	$ 10,700
Buildings and Improvements \| Maximum
Real Estate And Accumulated Depreciation
Period over which real estate assets are depreciated, maximum	40 years
Equipment \| Maximum
Real Estate And Accumulated Depreciation
Period over which real estate assets are depreciated, maximum	12 years
Mortgages
Real Estate And Accumulated Depreciation
Mortgage debts	$ 796,600

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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