Employee Benefit Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended					12 Months Ended									12 Months Ended															12 Months Ended									1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Other Assets	Dec. 31, 2012 Other Assets	Dec. 31, 2013 Defined Benefit Pension Plans	Dec. 31, 2012 Defined Benefit Pension Plans	Dec. 31, 2013 Defined Benefit Pension Plans Real estate Norway	Dec. 31, 2012 Defined Benefit Pension Plans Real estate Norway	Dec. 31, 2013 Defined Benefit Pension Plans Level 3 Inputs	Dec. 31, 2012 Defined Benefit Pension Plans Level 3 Inputs	Dec. 31, 2011 Defined Benefit Pension Plans Level 3 Inputs	Dec. 31, 2013 Defined Benefit Pension Plans Level 3 Inputs Real estate Norway	Dec. 31, 2012 Defined Benefit Pension Plans Level 3 Inputs Real estate Norway	Dec. 31, 2013 U.S. Defined Benefit Pension Plans	Dec. 31, 2012 U.S. Defined Benefit Pension Plans	Dec. 31, 2011 U.S. Defined Benefit Pension Plans	Dec. 31, 2013 Foreign Pension Plan Defined Benefit	Dec. 31, 2012 Foreign Pension Plan Defined Benefit	Dec. 31, 2011 Foreign Pension Plan Defined Benefit	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Canada BasisPoint	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Other Assets Norway	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Equity Securities Canada	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Equity Securities Norway	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Fixed Income Funds Canada	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Fixed Income Funds Norway	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Other Investments Canada	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Real estate Norway	Dec. 31, 2013 Foreign Pension Plan Defined Benefit Level 3 Inputs Norway	Dec. 31, 2013 OPEB	Dec. 31, 2012 OPEB	Dec. 31, 2011 OPEB	Dec. 31, 2013 CMRT U.S. Defined Benefit Pension Plans	Dec. 31, 2012 CMRT U.S. Defined Benefit Pension Plans	Dec. 31, 2011 CMRT U.S. Defined Benefit Pension Plans	Dec. 31, 2012 CMRT U.S. Defined Benefit Pension Plans Plan assets attributable to disposition of certain investments	Dec. 31, 2013 CMRT U.S. Defined Benefit Pension Plans Level 1 and Level 2	Dec. 31, 2012 CMRT U.S. Defined Benefit Pension Plans Level 1 and Level 2	Jan. 31, 2014 CMRT U.S. Defined Benefit Pension Plans Subsequent Event
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Defined contribution plan expense	$ 4.2	$ 3.9	$ 3.4
Expected contribution						27.4																								1.5
Discount rate															4.50%	3.60%		3.80%	3.70%											4.00%	3.47%
Expect to recognize unrecognized actuarial losses						11.4
Expect to recognize prior service credit\cost						0.5																								2.1
Expect to recognize transition obligations, Net						0.1
Percentage of average annual rate of return																																	14.00%
Long-term return on plan assets															10.00%	10.00%	10.00%	5.00%	5.20%	5.50%		4.00%		8.00%		4.00%		6.00%					10.00%	10.00%	10.00%				7.50%
Percentage of fair value of asset																																					83.00%	83.00%
Plan assets						496.6	460.6	4.8	5.5	261.5	238.1	200.6	4.8	5.5	54.9	50.7	45.4	441.6	409.9	343.7																254.7
Percentage of aggregate assets value	100.00%	100.00%		1.00%	35.00%
Average basis points of long-term rate of return on investment																					125
Percentage of plan asset allocation																							45.00%	12.00%	48.00%	78.00%	7.00%	9.00%
Percentage of assumed long-term rate of return for plan assets invested															10.00%	10.00%	10.00%	5.00%	5.20%	5.50%		4.00%		8.00%		4.00%		6.00%					10.00%	10.00%	10.00%				7.50%
Percentage of plan asset allocation																													8.00%
Weighted average discount rate used in determining the net periodic cost															3.60%	4.20%	5.10%	3.70%	4.90%	5.10%										3.47%	3.93%	4.65%
Curtailment																					7.1									(0.1)
Defined benefit plan, special termination benefits																					$ 0.2