Fair Value of Derivatives and Financial Instruments (Effect of Derivative Instruments on Consolidated Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Designated as Hedging Instrument \| Interest Expense
Derivative
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ 745	$ 193
Designated as Hedging Instrument \| Interest Rate Contract
Derivative
Unrealized (loss) gain from the effective portion of derivative instruments	(2,456)	832
Not Designated as Hedging Instrument \| Interest Expense
Derivative
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(524)	(2,644)
Parent Company [Member]
Derivative
Unrealized (loss) gain from the effective portion of derivative instruments	$ (2,456)	$ 832
Minimum [Member] \| Conventional Variable Rate Debt [Member]
Derivative
Debt Renewal Period	30 days
Maximum [Member] \| Conventional Variable Rate Debt [Member]
Derivative
Debt Renewal Period	90 days

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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+ References

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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