Income Tax Matters, Textuals (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Income Tax Contingency [Line Items]
Income tax provision	$ 9,200,000	$ 10,300,000	$ 33,100,000	$ 30,200,000
Effective tax rate	36.70%	28.90%	37.00%	28.10%
Increase (decrease) in unrecognized tax benefits, including interest and penalties		(2,700,000)
Increase (decrease) in effective tax rate due to unrecognized tax benefits, including interest and penalties		(7.70%)
Decrease in cash tax benefit from settlement of tax audit				(0.025)
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount			(2,700,000)
Effective Income Tax Rate Reconciliation, Tax Settlement, Foreign, Percent				(7.10%)
Effective Income Tax Rate Reconciliation, Tax Settlement, Foreign, Amount				(2,700,000)
Refund adjustment from settlement	(7,900,000)		(7,900,000)
Gross unrecognized tax benefits	3,700,000		3,700,000		3,800,000
Gross unrecognized tax benefits that would impact effective tax rate	2,600,000		2,600,000		2,700,000
Reduction in gross unrecognized tax benefits	1,500,000		1,500,000
Canada Revenue Agency Competent Authority [Member]
Income Tax Contingency [Line Items]
Decrease in cash tax benefit from settlement of tax audit				(7,700,000)
Audit & Advanced Pricing Agreement [Member]
Income Tax Contingency [Line Items]
Refund adjustment from settlement		$ 10,600,000		$ 10,600,000