QUARTERLY RESULTS OF OPERATIONS (Tables)

12 Months Ended

Dec. 31, 2018

Selected Quarterly Financial Information [Abstract]

The following is a summary of the unaudited quarterly results of operations for the years ended December 31, 2018 and 2017. Information about prior period acquisitions and the adoption of recent accounting pronouncements that may affect the comparability of the quarterly financial information presented below are included in Note 2 and Note 4.



	2018
	Mar. 31			Jun. 30			Sep. 30			Dec. 31
Revenues	$	273,718		$	297,018		$	305,525		$	315,571
Cost of revenues	62,477			67,136			72,072			68,248
Gross profit	211,241			229,882			233,453			247,323
Operating expenses	157,796			186,108			162,765			141,666
Income from operations	53,445			43,774			70,688			105,657
Interest and other income	2,987			2,652			3,035			4,607
Interest and other expense	(690		)	(728		)	(717		)	(695		)
Income before income taxes	55,742			45,698			73,006			109,569
Income tax expense	3,511			1,863			14,247			26,060
Net income	$	52,231		$	43,835		$	58,759		$	83,509
Net income per share — basic	$	1.46		$	1.22		$	1.63		$	2.31
Net income per share — diluted	$	1.44		$	1.20		$	1.61		$	2.29



	2017
	Mar. 31			Jun. 30			Sep. 30			Dec. 31
Revenues	$	226,553		$	237,153		$	247,533		$	253,991
Cost of revenues	51,346			55,273			55,483			58,301
Gross profit	175,207			181,880			192,050			195,690
Operating expenses	137,545			153,997			134,537			144,932
Income from operations	37,662			27,883			57,513			50,758
Interest and other income	429			605			555			2,455
Interest and other expense	(2,686		)	(2,693		)	(2,901		)	(734		)
Loss on debt extinguishment	—			—			—			(3,788		)
Income before income taxes	35,405			25,795			55,167			48,691
Income tax expense	13,275			3,611			20,990			4,487
Net income	$	22,130		$	22,184		$	34,177		$	44,204
Net income per share — basic	$	0.69		$	0.68		$	1.05		$	1.24
Net income per share — diluted	$	0.68		$	0.68		$	1.04		$	1.22