Quarterly Financial Information ( Unaudited ) (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2014 |
Sep. 30, 2014 |
Jun. 30, 2014 |
Mar. 31, 2014 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Revenue | |||||||||||
| Revenue | $ 43,252 | $ 37,092 | $ 35,238 | $ 34,612 | $ 30,756 | $ 28,407 | $ 24,744 | $ 26,332 | $ 150,194 | $ 110,239 | $ 83,127 |
| Costs and expenses: | |||||||||||
| Servicing and support | 8,749 | 7,845 | 7,903 | 7,550 | 7,012 | 6,598 | 7,000 | 6,248 | 32,047 | 26,858 | 22,718 |
| Technology and content development | 7,529 | 7,082 | 6,466 | 6,134 | 5,403 | 5,726 | 5,818 | 5,674 | 27,211 | 22,621 | 19,472 |
| Program marketing and sales | 20,231 | 21,567 | 21,526 | 19,587 | 16,296 | 16,971 | 16,710 | 15,241 | 82,911 | 65,218 | 54,103 |
| General and administrative | 10,064 | 8,477 | 8,871 | 6,711 | 5,973 | 6,303 | 5,708 | 5,436 | 34,123 | 23,420 | 14,840 |
| Total costs and expenses | 46,573 | 44,971 | 44,766 | 39,982 | 34,684 | 35,598 | 35,236 | 32,599 | 176,292 | 138,117 | 111,133 |
| Loss from operations | (3,321) | (7,879) | (9,528) | (5,370) | (3,928) | (7,191) | (10,492) | (6,267) | (26,098) | (27,878) | (28,006) |
| Other income (expense): | |||||||||||
| Interest expense | (173) | (127) | (126) | (126) | (119) | (176) | (134) | (784) | (552) | (1,213) | 27 |
| Interest income | 94 | 21 | 24 | 28 | 30 | 30 | 31 | 1 | 167 | 92 | 26 |
| Other | (250) | (250) | |||||||||
| Total other income (expense) | (79) | (356) | (102) | (98) | (89) | (146) | (103) | (783) | (635) | (1,121) | 53 |
| Net loss | $ (3,400) | $ (8,235) | $ (9,630) | $ (5,468) | $ (4,017) | $ (7,337) | $ (10,595) | $ (7,050) | $ (26,733) | $ (28,999) | $ (27,953) |
| Net Loss per Share | |||||||||||
| Basic and diluted (in dollars per share) | $ (0.07) | $ (0.20) | $ (0.23) | $ (0.13) | $ (0.10) | $ (0.18) | $ (0.27) | $ (0.92) | $ (0.63) | $ (0.91) | $ (3.81) |
| Weighted-average shares used in computing net loss per share: | |||||||||||
| Basic and diluted (in shares) | 45,651,475 | 41,645,894 | 41,362,476 | 40,978,741 | 40,577,087 | 40,269,937 | 39,304,884 | 7,698,709 | 42,420,356 | 32,075,107 | 7,432,055 |