NET INCOME (LOSS) PER SHARE (Tables)

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Calculation of basic and diluted net income (loss) per share

The following table sets forth the calculation of basic and diluted net income per share (in thousands except per share data):

	Year Ended December 31,
	2018		2017		2016
Numerator:
Net income	$	238,334	$	122,695	$	85,071
Denominator:
Denominator for basic net income per share — weighted-average outstanding shares	36,058		33,200		32,167
Effect of dilutive securities:
Stock options and restricted stock awards	390		359		269
Denominator for diluted net income per share — weighted-average outstanding shares	36,448		33,559		32,436
Net income per share — basic	$	6.61	$	3.70	$	2.64
Net income per share — diluted	$	6.54	$	3.66	$	2.62

Schedule of anti-dilutive securities excluded from computation of earnings per share

The following table summarizes the shares underlying the performance-based restricted stock awards and service-based restricted stock units excluded from the basic and diluted calculation (in thousands):

	Year Ended December 31,
	2018	2017	2016
Performance-based restricted stock awards	53	58	59
Service-based restricted stock units	1	1	1
Total shares excluded from computation	54	59	60