v3.6.0.2

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Jan. 31, 2013
Policies |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net (loss) income | $ (37,907) | $ (26,017) | $ (23,156) | $ (8,685) | $ (22,960) | $ (17,630) | $ (19,681) | $ (10,004) | $ (95,765) | $ (70,275) | $ (5,152) |  |  |
Accumulated deficit | 345,848 |  |  |  | 250,083 |  |  |  | 345,848 | 250,083 |  |  |  |
Cash and cash equivalents | 15,256 |  |  |  | 28,947 |  |  |  | 15,256 | 28,947 | $ 87,176 |  | $ 30,496 |
Short-term investments | 130,860 |  |  |  | 201,586 |  |  |  | 130,860 | 201,586 |  |  |  |
Outstanding debt with accrued interest | 49,624 |  |  |  | 42,090 |  |  |  | 49,624 | 42,090 |  |  |  |
Restricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash, current portion | 1,092 |  |  |  | 901 |  |  |  | 1,092 | 901 |  |  |  |
Restricted cash, long term portion | $ 342 |  |  |  | $ 683 |  |  |  | $ 342 | $ 683 |  |  |  |
"First Space" Sublease |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 800
"Second Space" Sublease |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash |  |  |  |  |  |  |  |  |  |  |  | $ 300 |  |

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