Derivative Financial Instruments - Recognized in Our Consolidated Balance Sheets and Consolidated Statements of Operations Related to Our FOREX Contracts Designated as Cash Flow Hedges (Detail) (FOREX Contracts [Member], Derivative Designated As Accounting Hedges [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in AOCGL on derivative (effective portion)	$ 6,519	$ (962)	$ 3,591
Contract drilling, excluding depreciation [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (loss) gain reclassified from AOCGL into income (effective portion)	(4,205)	10,351	1,790
Foreign Currency Transaction Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of loss recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	$ (17)	$ (85)	$ 0