Changes in Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Accumulated other comprehensive income
Balance	$ 296,456
Balance	322,734
Accumulated Other Comprehensive Income, net of taxes
Accumulated other comprehensive income
Balance	543	$ 25
Other comprehensive income before reclassifications	980	(15)
Amounts reclassified from accumulated other comprehensive income	153	(2)
Net current period change in other comprehensive income	1,133	(17)
Balance	$ 1,676	$ 8

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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