Gain or Loss on Sale of Investments (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale
Proceeds from sales and calls of investment securities		$ 167,660	$ 219,849	$ 181,971
Gross realized gains	[1]	1,877	501	3,723
Gross realized losses	[1]	(1,808)	(705)	(4,022)
Held-to-maturity
Proceeds from calls of investment securities		20,997	8,930	0
Gross realized gains	[1]	50	22	0
Gross realized losses	[1]	$ (100)	$ (6)	$ 0

[1] The gain or loss on the sale or call of each investment security is determined by the specific identification method.