Derivative Financial Instruments - Fair Value Hedges (Details) - Interest rate swaps - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net gains and losses recognized in income related to derivatives in fair value hedging relationships
Net losses recognized on fair value hedges	$ (1,436)	$ (2,402)	$ (3,901)
Minimum | Fair value hedges
Fair hedges carried
Fixed interest rate (as a percent)	2.59%
Maximum | Fair value hedges
Fair hedges carried
Fixed interest rate (as a percent)	5.70%
Net interest income | Fair value hedges
Net gains and losses recognized in income related to derivatives in fair value hedging relationships
Losses recorded	$ (1,226)	(2,472)	(3,673)
Noninterest income
Net gains and losses recognized in income related to derivatives in fair value hedging relationships
Recognized on derivatives	956	1,803	(2,022)
Recognized on hedged item	(1,166)	(1,733)	1,794
Net gains recognized on fair value hedges (ineffective portion)	(210)	70	$ (228)
Derivatives designated as hedging instruments
Fair hedges carried
Notional amounts	200,504	232,867
Derivatives designated as hedging instruments | Fair value hedges
Fair hedges carried
Notional amounts	50,500	82,900
Positive fair value	0	0
Fair value losses	$ 1,500	$ 2,400