Changes in Accumulated Other Comprehensive Income (Loss) Balances (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 5,898
Reclassification to the income statement	(959)
Change in fair value	7,084
Ending Balance	12,023
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	6,991
Change in fair value	2,554
Ending Balance	9,545
Cash Flow Hedging
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(1,093)
Reclassification to the income statement	(959)
Change in fair value	4,530
Ending Balance	$ 2,478