Quarterly Financial Information (unaudited) (Tables)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

The following table contains selected financial information from unaudited statements of income for each quarter of 2016 and 2015.

	Quarters Ended
	2016								2015
	Dec. 31		Sept. 30		June 30		Mar. 31		Dec. 31(b)		Sept. 30		June 30		Mar. 31
Revenues	$	193,281	$	194,497	$	188,972	$	179,293	$	158,916	$	150,845	$	146,295	$	134,966
Gross profit	92,817		93,480		86,936		82,118		73,222		71,833		68,253		63,879
Income before income taxes (a)	35,119		36,419		30,195		27,574		19,540		31,744		29,781		27,359
Net income (a)	31,196		35,430		25,007		18,224		8,618		20,142		18,836		17,273
Earnings per diluted share	$	0.80	$	0.91	$	0.65	$	0.47	$	0.23	$	0.55	$	0.52	$	0.48
Shares used in computing diluted    earnings per share (a)	38,975		39,062		38,738		39,071		37,864		36,349		36,097		35,895

(a) During fourth quarter 2016, we adopted ASU No. 2016-09 requiring the recognition of excess tax benefits as a component of income tax expense; these benefits were historically recognized in equity. As the standard required a prospective method of adoption, our fourth quarter 2016 net income includes a $9.2 million income tax benefit due to the adoption that did not occur in the comparable prior year periods presented above. The three months ended March 31, June 30, and September 30, 2016, respectively, have been adjusted for the newly adopted standard. Refer to Note 1 "Summary of Significant Accounting Policies" for further discussion of this new accounting standard.

(b) Operating results for the three months ended December 31, 2015, include $5.9 million for financial advisory, legal, accounting, due diligence, valuation and other expenses necessary to complete the NWS acquisition as well as $3.5 million amortization expense related to NWS acquisition intangibles.