Components of Interest Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Component of Other Expense, Nonoperating [Line Items]
Interest on borrowings and related fees	$ 14,289	$ 13,120	$ 28,306	$ 23,867
Accretion on original issue discount	341	583	674	2,788
Amortization of debt issuance costs	694	895	1,376	1,962
Capitalized interest	(240)	(455)	(498)	(990)
Interest expense	$ 15,084	$ 14,143	$ 29,858	$ 27,627