Derivative Instruments and Balance Sheet Offsetting - Net Gains (Losses) Recorded in Other Comprehensive Income and the Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivative instruments
Unrealized losses on interest rate swaps expected to be reclassified during next twelve months	$ 2,900
Interest rate swaps \| Derivatives designated as hedging instruments:
Derivative instruments
Amount of gain (loss) recognized in other comprehensive income	(7,552)	$ 7,963
Amount of gain (loss) reclassified from other comprehensive income to interest income or expense	$ 1,288	$ (242)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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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).

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