Income Taxes (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Income Taxes (Textual) [Abstract]
Income taxes paid	$ 5,300,000		$ 36,300,000		$ 48,900,000
Deferred tax assets	631,000		654,000
Deferred tax asset related to U.S. foreign tax credit	500,000		2,900,000
Valuation allowance amount	0		0
Deferred other tax expense	1,400,000
Deferred income tax expense	40,374,000		16,503,000		5,473,000
Accumulated other comprehensive loss	(21,181,000)	[1]	(45,379,000)	[1]
Amount from exercise of awards	0
Tax benefit realized from the exercise of awards	1,300,000		400,000.0
Interest and penalties accrued	200,000		100,000
Interest and penalties expense	(100,000)		100,000
State
Income Taxes (Textual) [Abstract]
Operating loss carryforwards with expiration date	12,400,000
Deferred tax assets	500,000
Operating loss carryforwards valuation allowance	100,000		0
Operating loss carryforwards			600,000
Canadian
Income Taxes (Textual) [Abstract]
Deferred tax assets	100,000
Operating loss carryforwards valuation allowance	0		0
Operating loss carryforwards	400,000
Deferred tax asset with respect to Canadian net operating loss carryforwards			100,000
Retiree Health Care Plan Liability and Medicare Part D Subsidy Error | Restatement Adjustment
Income Taxes (Textual) [Abstract]
Deferred income tax expense	(1,400,000)
Accumulated other comprehensive loss	$ 1,400,000

[1] All amounts are net of tax. Amounts in parentheses indicate debits