Annual report pursuant to Section 13 and 15(d)

Selected Quarterly Financial Data (Details)

v3.10.0.1
Selected Quarterly Financial Data (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Disaggregation of Revenue [Line Items]                      
Total revenue                 $ 869,480 $ 670,963 $ 568,128
Gross profit $ 129,482 $ 130,467 $ 125,183 $ 120,169 $ 111,132 $ 97,767 $ 92,700 $ 89,066 505,301 390,665 324,920
Net income $ 6,272 $ 9,073 $ 8,479 $ 10,901 $ (20,865) $ 6,834 $ 6,213 $ 8,195 $ 34,725 $ 377 $ 16,650
Net income (loss) per share attributable to common stockholders:                      
Basic (in dollars per share) $ 0.07 $ 0.10 $ 0.10 $ 0.13 $ (0.26) $ 0.09 $ 0.08 $ 0.10 $ 0.40 $ 0.00 $ 0.22
Diluted (in dollars per share) $ 0.07 $ 0.09 $ 0.09 $ 0.13 $ (0.26) $ 0.08 $ 0.08 $ 0.10 $ 0.38 $ 0.00 $ 0.21
On demand                      
Disaggregation of Revenue [Line Items]                      
Total revenue $ 218,051 $ 215,413 $ 206,945 $ 193,300 $ 180,104 $ 161,578 $ 154,727 $ 146,213 $ 833,709 $ 642,622 $ 542,531
Professional and other                      
Disaggregation of Revenue [Line Items]                      
Total revenue 8,923 9,540 9,307 8,001 7,576 7,480 6,579 6,706 35,771 28,341 25,597
Service                      
Disaggregation of Revenue [Line Items]                      
Total revenue $ 226,974 $ 224,953 $ 216,252 $ 201,301 $ 187,680 $ 169,058 $ 161,306 $ 152,919 $ 869,480 $ 670,963 $ 568,128