Quarterly Financial Information (unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

QUARTERLY FINANCIAL INFORMATION (unaudited)

The following table contains selected financial information from unaudited statements of income for each quarter of 2018 and 2017:



	Quarters Ended
	2018								2017 (As Adjusted)
	Dec. 31		Sept. 30		June 30		Mar. 31		Dec. 31(a)		Sept. 30		June 30		Mar. 31
Revenues	$	241,981	$	236,067	$	236,060	$	221,174	$	217,701	$	214,706	$	208,763	$	199,729
Gross profit	115,871		111,626		109,276		102,805		105,350		103,989		95,503		94,535
Income before income taxes	40,107		38,626		37,700		39,437		45,261		44,357		37,197		36,641
Net income	31,552		38,924		39,161		37,825		66,196		38,836		31,770		32,769
Earnings per diluted share	$	0.79	$	0.96	$	0.97	$	0.95	$	1.68	$	0.99	$	0.81	$	0.84
Shares used in computing diluted earnings per share	39,891		40,528		40,224		39,836		39,499		39,342		39,201		38,932

(a) The fourth quarter of 2017 includes the significant impact of the enactment of the Tax Act. The most significant impact of the Tax Act to us is the reduction in the U.S. federal corporate income tax rate from 35% to 21%. The impact of the rate reduction on our 2017 income tax provision is a $26.0 million tax benefit due to the remeasurement of deferred tax assets and liabilities. Refer to Note 7 - "Income Tax" for further discussion on the impact the Tax Act.