Currency Transaction Gains/Losses (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Currency Transaction Gains (Losses) [Line Items]
Net transaction gains	$ 37,572	$ 63,519	$ 32,451
Operating income
Currency Transaction Gains (Losses) [Line Items]
Net transaction gains	38,842	61,956	34,299
Other non-operating (expense) income, net
Currency Transaction Gains (Losses) [Line Items]
Net transaction gains	$ (1,270)	$ 1,563	$ (1,848)