Effective Rate for Income from Operations Before Income Taxes (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Effective Tax Rates Line Items
Effective tax rates	54.40%	(58.50%)	30.20%
U.S.
Schedule Of Effective Tax Rates Line Items
Effective tax rates	64.50%	249.70%	495.10%
Foreign
Schedule Of Effective Tax Rates Line Items
Effective tax rates	57.70%	24.40%	21.60%