Summary of Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Effect of Derivative Instruments on Consolidated Statements of Income and Consolidated Statements of Comprehensive Income
Realized loss on derivative instruments, net	$ (704)	$ (248)
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Other comprehensive (income) loss
Effect of Derivative Instruments on Consolidated Statements of Income and Consolidated Statements of Comprehensive Income
Designated interest rate swaps	16,467	(15,813)
Gain (Loss) on Derivative Instruments [Member] \| Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Effect of Derivative Instruments on Consolidated Statements of Income and Consolidated Statements of Comprehensive Income
Realized loss on derivative instruments, net	704	248
Unrealized (Gain) Loss On Derivative Instruments [Member] \| Interest Rate Cap [Member]
Effect of Derivative Instruments on Consolidated Statements of Income and Consolidated Statements of Comprehensive Income
Non-designated interest rate swaps	(986)	1,186
Interest and Debt Expense \| Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Effect of Derivative Instruments on Consolidated Statements of Income and Consolidated Statements of Comprehensive Income
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 2,355	$ 1,824

Derivative Instrument, Amortization of Interest Rate

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+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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