Investments in Real Estate and Real Estate Under Construction - Narrative (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016 USD ($) Property	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Aggregate acquisition expenses	$ 214	$ 714
Construction in progress	108,763		$ 95,402
Proceeds from sale of real estate	$ 131,985	78,857
Number of real estate properties held for sale \| Property	3
Real estate, at cost	$ 21,776		16,590
Real estate, other assets	283		0
Real estate, other liabilities	0		8,373
LCIF [Member]
Business Acquisition [Line Items]
Construction in progress	24,166		9,223
Proceeds from sale of real estate	69,038	$ 0
Impairment of real estate	2,426
Certain Properties [Member] \| LCIF [Member]
Business Acquisition [Line Items]
Proceeds from sale of real estate	103,265
Gain on sale of properties	16,029
Payments of debt extinguishment costs	$ 1,615
Number of real estate properties held for sale \| Property	1
Real estate, at cost	$ 3,885
Real estate, other assets	20
Real estate, other liabilities	161
Development Deals [Member]
Business Acquisition [Line Items]
Capitalized interest	$ 3,985		$ 2,726

Disposal Group, Including Discontinued Operation, Real Estate, At Cost

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Number of Real Estate Properties, Held For Sale

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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The current amount of expenditures for a real estate project that has not yet been completed.

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Amount classified as other assets attributable to disposal group held for sale or disposed of.

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Amount classified as other liabilities attributable to disposal group held for sale or disposed of.

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Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of interest capitalized during the period.

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The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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