Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Consolidated Statements of Comprehensive Income
Net income	$ 25,140	$ 19,327	$ 73,938	$ 54,189
Unrealized gains (losses) on securities:
Unrealized holding gains (losses) arising during period	5,991	(2,877)	2,981	13,287
Tax effect	(2,284)	1,097	(1,137)	(5,066)
Reclassification adjustment for gains (losses) included in net income		90		2
Tax effect		(34)		(1)
Net of tax amount	3,707	(1,724)	1,844	8,222
Unrealized gains (losses) on derivative financial instruments qualifying as cash flow hedges:
Unrealized holding gains (losses) arising during period	(154)	41	(245)	(144)
Tax effect	59	(16)	93	55
Reclassification adjustment for losses included in interest expense	89	78	230	232
Tax effect	(34)	(30)	(88)	(88)
Net of tax amount	(40)	73	(10)	55
Change in pension and retiree medical plan obligation:
Reclassification adjustment for actuarial (gains) losses included in salaries and employee benefits	225	165	674	495
Tax effect	(86)	(63)	(256)	(190)
Net of tax amount	139	102	418	305
Other comprehensive income (loss), net of tax	3,806	(1,549)	2,252	8,582
Comprehensive income	$ 28,946	$ 17,778	$ 76,190	$ 62,771