Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Company Estimated Grant-date Fair Value of Stock Options Granted Using Black-Scholes Option Valuation Model

The Company estimated the grant-date fair value of stock options granted using the Black-Scholes option valuation model with the following assumptions:

	2011
Expected dividend yield		0.0%
Expected volatility		47.2%
Risk-free interest rate		2.4%-2.9%
Expected life		6.5 years

Summary of Stock-based Compensation Expense

Stock-based compensation expense is summarized as follows:

	Years Ended December 31,
	2012		2011		2010
($ in thousands)
Stock-based compensation expense	$	6,927	$	5,625	$	3,894

Summary of Stock Option Activity

Stock option activity for the year ended December 31, 2012 is summarized as follows:

	Number of shares			Weighted Average Exercise Price
Outstanding at December 31, 2011		352,942		$	20.21
Granted		—		$	—
Exercised		(130,304	)	$	20.23
Forfeited		(2,289	)	$	37.01
Outstanding at December 31, 2012		220,349		$	20.03
Vested and exercisable at December 31, 2012		195,380		$	18.31
Options expected to vest at December 31, 2012		21,985		$	33.49

Summary of Restricted Stock Units Activity

RSU activity for the year ended December 31, 2012 is summarized as follows:

	Number of shares			Weighted Average Grant Date Fair Value
Outstanding at December 31, 2011		576,704		$	24.16
Granted		102,531		$	81.47
Forfeited		(4,907	)	$	50.12
Settled		(382,271	)	$	13.52
Outstanding at December 31, 2012		292,057		$	57.89