Reconciliation of Beginning and Ending Balance for Liabilities Measured at Fair Value on Recurring Basis Unobservable Inputs (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balances - Liabilities	$ 7,259	$ 10,435	$ 9,176	$ 14,192
Total loss included in accumulated other comprehensive loss	112	1,282	1,180	405
Settlements	(1,533)	(1,467)	(4,518)	(4,347)
Ending balances - Liabilities	$ 5,838	$ 10,250	$ 5,838	$ 10,250