CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 11,136us-gaap_NetIncomeLoss	$ 9,912us-gaap_NetIncomeLoss
Change in securities available for sale:
Unrealized holding gain (loss) on securities available for sale arising during the period	3,662	4,791
Reclassification adjustment for (gains) losses included in net income	(42)	0
Net securities gain (loss) activity during the period	3,620	4,791
Tax effect	(1,443)	(1,904)
Net of tax amount	2,177	2,887
Defined benefit pension plans:
Net gain (loss) on defined benefit pension plans	(276)	64
Amortization of net actuarial loss	61	49
Net gain (loss) activity during the period	(215)	113
Tax effect	77	(52)
Net of tax amount	(138)	61
Total other comprehensive income (loss), net of tax	2,039	2,948
Comprehensive income	$ 13,175us-gaap_ComprehensiveIncomeNetOfTax	$ 12,860us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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