Schedule Of Income Tax Expense (Benefit) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Line Items]
Federal		$ (57)	$ (19,190)
State	813	1,150	390
Total	813	1,093	(18,800)
Federal	11,922	27,940	(5,045)
State	(182)	2,755	(948)
Total	11,590	30,695	(5,993)
Total income tax expense (benefit)	10,927	31,788	(24,793)
Deferred Income Taxes
Income Taxes [Line Items]
Total	$ 11,740	$ 30,695	$ (5,993)