Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 5,343us-gaap_ProfitLoss	$ 4,548us-gaap_ProfitLoss
Other comprehensive income (loss):
Change in net actuarial gain	26	40
Tax effect on change in net actuarial gain	(9)	(14)
Unrealized holding gains (losses) arising during the period	7,069	(1,646)
Tax effect on unrealized holding gains (losses) arising during the period	(2,474)	576
Reclassification adjustment for gains included in net income	(861)	(185)
Tax effect on reclassification adjustment for gains included in net income	301	65
Other comprehensive income (loss), net of tax	4,052	(1,164)
Comprehensive income	$ 9,395	$ 3,384

Other comprehensive income adjustment to recognize changes in actuarial assumptions arising during period before tax.

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Other comprehensive income change in net actuarial gain loss tax.

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Other comprehensive income reclassification adjustments for unrealized holding gains losses before tax.

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

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

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

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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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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