Derivatives and Hedging Activities - Effect of derivatives in fair value hedging relationships (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Deposit interest expense	$ 15,075	$ 15,957
Fair value hedging \| Interest expense - deposits
Gains (losses) on fair value hedging relationships:
Amounts related to interest settlements on derivatives	(75)	(101)
Recognized on derivatives	1,062	451
Recognized on hedged items	(982)	(462)
Net income (expense) recognized on fair value hedges	$ 5	$ (112)

Gain (Loss) On Derivative Interest Settlement

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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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.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Aggregate amount of interest expense on all deposits.

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