Basis of Presentation (Tables)

6 Months Ended

Jun. 30, 2014

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Reconciliation of basic earnings per share ("EPS") to diluted EPS

The following is a reconciliation of basic earnings per common share to diluted earnings per share:

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands, except per share amounts)	2014		2013		2014		2013
Net income available to common stockholders	$	20,451	$	18,502	$	32,538	$	23,297
Basic weighted-average shares outstanding	49,011		48,529		48,955		48,532
Dilutive effect of potential common stock equivalents — stock options and restricted stock units	216		99		191		95
Diluted weighted-average shares outstanding	49,227		48,628		49,146		48,627
Earnings per common share:
Basic	$	0.42	$	0.38	$	0.66	$	0.48
Diluted	$	0.42	$	0.38	$	0.66	$	0.48
Potentially dilutive securities excluded from earnings per diluted share because their effect is anti-dilutive	—		—		—		—

Stock option and restricted stock unit activity of the entity

The following table represents the Company’s stock option and restricted stock unit activity for the three and six months ended June 30,2014 and 2013:

	Three Months Ended June 30,						Six Months Ended June 30,
(in thousands)	2014			2013			2014			2013
Stock-based compensation expense recognized in operating expenses	$	3,264		$	2,807		$	5,740		$	5,686
Tax benefit of stock-based compensation expense in provision for income taxes	1,163			896			2,073			1,944
Stock-based compensation expense, net of tax	$	2,101		$	1,911		$	3,667		$	3,742
Fair value of shares vested	$	3,312		$	2,836		$	5,691		$	5,649
Proceeds to the Company from the exercise of stock-based compensation	$	857		$	280		$	2,626		$	776
Tax effect from the exercise of stock-based compensation, including shortfall tax benefits	$	(51	)	$	(7	)	$	(186	)	$	(1,850	)

	At June 30,
(in thousands)	2014		2013
Stock-based compensation cost capitalized in inventory	$	508	$	384

Summary of financial instruments

The balances of the Company’s primary financial instruments were as follows:

	At June 30,				At December 31
(in thousands)	2014		2013		2013
Financial instruments	$	96,996	$	60,725	$	117,571

Schedule of effective tax rates and income tax expense

The following table presents the Company’s effective tax rates and income tax expense for the three and six months ended June 30,2014 and 2013:

	Three Months Ended June 30,						Six Months Ended June 30,
(in thousands, except percentages)	2014			2013			2014			2013
Effective tax rate	36.3		%	37.7		%	37.2		%	39.8		%
Provision for income taxes	$	11,667		$	11,177		$	19,271		$	15,434