Long-Term Debt Credit Facility Agreements (Detail)	3 Months Ended		12 Months Ended					12 Months Ended		12 Months Ended			12 Months Ended							0 Months Ended				0 Months Ended			0 Months Ended			0 Months Ended		3 Months Ended
	Mar. 31, 2013 USD ($)	Jun. 30, 2012 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2013 U S Term Loans [Member] USD ($)	Dec. 31, 2012 U S Term Loans [Member] USD ($)	Dec. 31, 2013 Canadian Term Loans [Member] CAD	Dec. 31, 2012 Canadian Term Loans [Member] CAD	Dec. 31, 2013 Term Loan [Member] USD ($)	Dec. 31, 2013 Euro Term Loans [Member] EUR (€)	Dec. 31, 2012 Euro Term Loans [Member] EUR (€)	Dec. 31, 2013 Term Loan Facility [Member]	Dec. 31, 2013 Term Loan Facility [Member] EUR (€)	Dec. 31, 2012 Term Loan Facility [Member] USD ($)	Dec. 31, 2011 Term Loan Facility [Member] USD ($)	Dec. 31, 2013 Revolving Loan [Member] USD ($)	Dec. 31, 2012 Revolving Loan [Member]	Dec. 31, 2011 Revolving Loan [Member]	Jan. 14, 2014 Subsequent Event [Member] USD ($)	Jan. 14, 2014 Subsequent Event [Member] U S Term Loans [Member] USD ($)	Jan. 14, 2014 Subsequent Event [Member] Canadian Term Loans [Member] CAD	Jan. 14, 2014 Subsequent Event [Member] Euro Term Loans [Member] EUR (€)	Jan. 14, 2014 Subsequent Event [Member] Revolving Loan [Member] USD ($)	Jan. 14, 2014 Subsequent Event [Member] U S Revolving Loans [Member] USD ($)	Jan. 14, 2014 Subsequent Event [Member] Canadian Revolving Loans [Member] CAD	Jan. 14, 2014 Subsequent Event [Member] Revolving And Term Loans [Member] London Interbank Offered Rate [Member]	Jan. 14, 2014 Subsequent Event [Member] Revolving And Term Loans [Member] Base Rate [Member]	Jan. 14, 2014 Subsequent Event [Member] Maximum [Member] USD ($)	Jan. 14, 2014 Subsequent Event [Member] Maximum [Member] Revolving Loan [Member]	Jan. 14, 2014 Subsequent Event [Member] Minimum [Member] Revolving Loan [Member]	Mar. 31, 2014 Scenario, Forecast [Member] Credit Facility 2005 [Member] USD ($)
Debt Instrument [Line Items]
Long-term debt, due in the next twelve months			$ 126,159,000							$ 20,000,000
Borrowings outstanding under the credit agreement						364,000,000	520,000,000	68,900,000	81,000,000		234,500,000	335,000,000		752,200,000	1,044,800,000	0					365,000,000	70,000,000	220,000,000
Letter of credit outstanding under the credit agreement																	22,700,000
Borrowings available under the revolving loan facilities						766,700,000		10,000,000
Repayments of long-term debt			308,257,000	285,932,000	691,427,000	156,000,000		12,200,000		300,900,000	100,500,000
Debt, Weighted Average Interest Rate													2.00%	2.00%	2.20%	2.80%	1.90%	1.70%	2.50%
Weighted average interest rate after interest rate swap													2.70%	2.70%	2.60%	3.30%
Line of Credit Facility, Maximum Borrowing Capacity																									986,000,000	15,000,000
Additional borrowing capacity																				1,250,000,000									625,000,000
Line of credit facility, margin																											1.50%	0.50%
Line of Credit Facility, Interest Rate at Period End																					1.74%	2.76%	1.74%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage																								0.25%						0.35%	0.20%
Letter Of Credit Maximum Borrowing Amount																								200,000,000
Letters Of Credit Facing Fee																				500
Letters Of Credit Facing Fee Percentage																				0.25%
Loss on early extinguishment of debt	$ (2,100,000)	$ (38,700,000)	$ (2,068,000)	$ (38,704,000)	$ (976,000)					$ (2,100,000)																						$ (1,600,000)