Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Comprehensive Income
Net income	$ 1,615	$ 1,845	$ 23,991
Other comprehensive income (loss):
Adjustment to pension liability	1,345	921
Tax expense	(538)	(368)
Adjustment to pension liability, net of tax	807	553
Foreign currency translation adjustment	(1,487)	186
Total other comprehensive income (loss), net of tax	(680)	739
Comprehensive income	935us-gaap_ComprehensiveIncomeNetOfTax	2,584us-gaap_ComprehensiveIncomeNetOfTax
Accumulated other comprehensive income
Balance at beginning of period	(47,229)	(28,118)	(28,118)
Other comprehensive income (loss), net of tax, before reclassifications	(1,487)	186
Amounts reclassified from accumulated other comprehensive income, net of tax	807	553
Net current period other comprehensive income (loss), net of tax	(680)	739	(19,111)
Balance at end of period	(47,909)	(27,379)	(47,229)
Defined Benefit Pension Items
Accumulated other comprehensive income
Balance at beginning of period	(49,560)	(32,279)	(32,279)
Amounts reclassified from accumulated other comprehensive income, net of tax	807	553
Net current period other comprehensive income (loss), net of tax	807	553
Balance at end of period	(48,753)	(31,726)
Foreign Currency Items
Accumulated other comprehensive income
Balance at beginning of period	2,331	4,161	4,161
Other comprehensive income (loss), net of tax, before reclassifications	(1,487)	186
Net current period other comprehensive income (loss), net of tax	(1,487)	186
Balance at end of period	$ 844	$ 4,347

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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