Guarantor Disclosures - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012
Condensed Financial Statements, Captions [Line Items]
Ownership interest in guarantor subsidiaries	100.00%
6 5/8% Senior Notes Due 2016
Condensed Financial Statements, Captions [Line Items]
Maturity	2016
Minimum debt amount guaranteed by subsidiaries	$ 5,000