Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2013

Weighted-Average Assumptions Used to Estimate Grant Date Fair Values for Stock Options Granted

Weighted-average assumptions used to estimate the grant date fair values for stock options granted for the three and six month periods ended June 30, 2013 and 2012 follow:

	Three Months Ended June  30,						Six Months Ended June  30,
	2013			2012			2013			2012
Volatility		40.90	%		48.86	%		41.36	%		48.85	%
Expected term (in years)		5.00			5.00			5.00			5.00
Dividend yield		0.87	%		1.22	%		0.89	%		1.21	%
Risk-free interest rate		0.70	%		0.88	%		0.70	%		0.88	%

Stock Option Activity

Stock option activity from January 1, 2013 to June 30, 2013 follows:

	Underlying Shares			Weighted Average Exercise Price
Outstanding at January 1, 2013		7,827,195		$	20.35
Granted		692,500		$	22.51
Exercised		(1,190,000	)	$	16.21
Cancelled		(10,000	)	$	18.63
Expired		—			—
Outstanding at June 30, 2013		7,319,695		$	21.23
Exercisable at June 30, 2013		6,044,555		$	21.30

Restricted Stock Activity

Restricted stock activity from January 1, 2013 to June 30, 2013 follows:

	Shares			Weighted Average Grant Date Fair Value
Non-vested restricted stock outstanding at January 1, 2013		1,279,146		$	20.03
Granted		862,250		$	21.70
Vested		(561,669	)	$	20.02
Forfeited		(31,963	)	$	19.50
Non-vested restricted stock outstanding at June 30, 2013		1,547,764		$	20.98

Restricted Stock Unit Activity

Restricted stock unit activity from January 1, 2013 to June 30, 2013 follows:

	Shares			Weighted Average Grant Date Fair Value
Non-vested restricted stock units outstanding at January 1, 2013		17,670		$	20.08
Granted		11,250		$	21.09
Vested		(8,664	)	$	20.01
Forfeited		—			—
Non-vested restricted stock units outstanding at June 30, 2013		20,256		$	20.67

Stock-Settled Performance Units

The total target number of shares with respect to the Stock-Settled Performance Units is set forth below:

	2013 Performance Unit Awards		2012 Performance Unit Awards		2011 Performance Unit Awards		2010 Performance Unit Awards
Target number of shares		236,500		192,000		144,375		178,750

Fair value of Stock-Settled Performance Units

The fair value of the Stock-Settled Performance Units is set forth below (in thousands):

	2013 Performance Unit Awards		2012 Performance Unit Awards		2011 Performance Unit Awards		2010 Performance Unit Awards
Fair value at date of grant	$	5,564	$	3,065	$	5,569	$	3,117

Compensation Expense Associated with Stock-Settled Performance Units

Compensation expense associated with the Stock-Settled Performance Units is shown below (in thousands):

	2013 Performance Unit Awards		2012 Performance Unit Awards		2011 Performance Unit Awards		2010 Performance Unit Awards
Three months ended June 30, 2012		NA	$	255	$	464	$	260
Three months ended June 30, 2013	$	464	$	255	$	464		NA
Six months ended June 30, 2012		NA	$	255	$	928	$	520
Six months ended June 30, 2013	$	464	$	510	$	928	$	260