Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Income Tax [Line Items]
Deferred tax assets, operating loss carryforwards	$ 69.1
Operating loss carryforwards, deferred tax assets valuation allowance	99.0	17.3
Maturity period for net operating loss carryovers	1 to 20 years
Maturity period for tax credit carryovers	1 to 10 years
Valuation allowances for certain tax credit carryovers	11.5	14.9
Valuation allowances for potential capital losses	4.9	2.7
Maturity period for net Capital loss carryovers	2 to 4 years
Valuation allowances for net Capital loss carryovers	7.4	7.8
Net operating loss carryovers expire with in the period	47.8
Unremitted earnings of foreign subsidiaries	3,204.0
Unrecognized tax benefits income tax penalties and interest expense recognized	5.7	8.2	23.2
Recognized liability for interest and penalties	47.8	42.1	33.9
Examination period for state income tax returns	3 to 5 years
Foreign jurisdictions statutes of limitation period	3 to 5 years
State examination period after notification	Up to one year
Luxembourg Inland Revenue [Member]
Income Tax [Line Items]
Deferred tax assets, operating loss carryforwards				70.5
Operating loss carryforwards, deferred tax assets valuation allowance				$ 70.5