Schedule Of Share-Based Payment Award Activity (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at beginning of period, number of options	0	5,473	73,413
Granted, number of options
Exercised, number of options		(325)	(67,940)
Adjustment, number of options
Forfeited, number of options
Expired / Cancelled, number of options		(5,148)
Outstanding at end of period, number of options	0	0	5,473
Options Exercisable at end of period, number of options	0	0	5,473
Outstanding at beginning of period, weighted average exercise price	$ 0.00	$ 5.01	$ 13.28
Granted, weighted average exercise price
Exercised, weighted average exercise price		$ 5.00	$ 13.95
Adjustment, weighted average exercise price
Forfeited, weighted average exercise price
Expired / canceled, weighted average exercise price		$ 5.01
Outstanding at end of period, weighted average exercise price	$ 0.00	$ 0.00	$ 5.01
Options Exercisable at end of period, weighted average exercise price	$ 0.00	$ 0	$ 5.01
Outstanding at end of period, weighted average remaining contractual term	0 years	0 years	18 days
Options Exercisable at end of period, weighted average remaining contractual term	0 years	0 years	18 days
Outstanding at end of period, aggregate intrinsic value	$ 0	$ 0	$ 234
Options Exercisable at end of period, aggregate intrinsic value	$ 0	$ 0	$ 234