CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 9,298		$ 7,421
Securities available for sale:
Changes in fair value in securities available for sale	612		(1,053)
Net losses (gains) on securities reclassified into earnings	0	[1]	393	[1]
Net change in fair value of securities available for sale	612		(660)
Reclassification adjustment for other-than-temporary impairment losses transferred into earnings	0	[2]	1,384	[2]
Cash flow hedges:
Change in fair value of cash flow hedges	(16)		(2)
Net cash flow hedge losses reclassified into earnings	92	[3]	122	[3]
Net change in fair value of cash flow hedges	76		120
Defined benefit plan obligation adjustment	88	[4]	337	[4]
Total other comprehensive (loss) income, net of tax	776		1,181
Total comprehensive income	$ 10,074		$ 8,602

[1] Reported as total other-than-temporary impairment losses on securities in the Consolidated Statements of Income.

[2] Reported as the portion of loss recognized in other comprehensive income in the Consolidated Statements of Income.

[3] Included in interest expense on junior subordinated debentures in the Consolidated Statements of Income.

[4] Included in salaries and employee benefits expense in the Consolidated Statements of Income.