Share-Based Compensation - Schedule of Restricted Stock Units Activity (Detail) (Restricted Stock Units [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Vested And Nonvested Restricted Stock Units Activity [Line Items]
Weighted Average Grant Date Fair Value, RSUs, Beginning balance	$ 30.00
Weighted Average Grant Date Fair Value, RSUs, Granted	$ 26.98	$ 30.00
Weighted Average Grant Date Fair Value, RSUs, Vested	$ 30.00
Weighted Average Grant Date Fair Value, RSUs, Cancelled	$ 26.99
Weighted Average Grant Date Fair Value, RSUs, Ending balance	$ 27.03	$ 30.00
RSUs outstanding, Beginning Balance	80
RSUs outstanding, Granted	4,647	80
RSUs outstanding, Vested	(4)
RSUs outstanding, Cancelled	(239)
RSUs outstanding, Ending Balance	4,484	80
Time Based Stock Options and SARs [Member]
Vested And Nonvested Restricted Stock Units Activity [Line Items]
RSUs outstanding, Beginning Balance	80
RSUs outstanding, Granted	3,162	80
RSUs outstanding, Vested	(4)
RSUs outstanding, Cancelled	(164)
RSUs outstanding, Ending Balance	3,074	80
Performance Based Stock Options and RSUs [Member]
Vested And Nonvested Restricted Stock Units Activity [Line Items]
RSUs outstanding, Beginning Balance
RSUs outstanding, Granted	1,485
RSUs outstanding, Vested
RSUs outstanding, Cancelled	(75)
RSUs outstanding, Ending Balance	1,410