Stockholders' Equity and EPS (Tables)

12 Months Ended

Dec. 31, 2012

Equity and Earnings Per Share [Abstract]

Reconciliation of Basic EPS to Diluted EPS

The following is a reconciliation of basic EPS to diluted EPS for 2012, 2011 and 2010:

	Year ended December 31,
(Dollars and shares in thousands, except per share amounts)	2012		2011		2010
Numerator:
Net income available to common stockholders	$	175,103	$	171,902	$	94,951
Denominator:
Weighted average common shares outstanding-basic	44,242		43,004		41,774
Weighted average effect of dilutive securities:
Stock options and ESPP	370		517		641
Restricted stock units	152		116		63
Denominator for diluted calculation	44,764		43,637		42,478
Earnings per common share:
Basic	$	3.96	$	4.00	$	2.27
Diluted	$	3.91	$	3.94	$	2.24

Common Shares Excluded from Diluted EPS Calculation as They Were Deemed to be Anti-Dilutive

The following table summarizes the weighted-average common shares excluded from the diluted EPS calculation as they were deemed to be antidilutive for 2012, 2011 and 2010:

	Year ended December 31,
(Shares in thousands)	2012	2011	2010
Stock options	695	944	1,334
Restricted stock units	—	149	—
Total	695	1,093	1,334