Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statements Of Comprehensive Income (Loss) [Abstract]
Net income	$ 29,355us-gaap_ProfitLoss	$ 25,530us-gaap_ProfitLoss	$ 23,449us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Net unrealized (losses) gains on securities available for sale	6,962	(21,397)	2,490
Pension and post-retirement obligations	(5,786)	7,957	(182)
Total other comprehensive income (loss), net of tax	1,176	(13,440)	2,308
Comprehensive income	$ 30,531us-gaap_ComprehensiveIncomeNetOfTax	$ 12,090us-gaap_ComprehensiveIncomeNetOfTax	$ 25,757us-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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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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