Fair Value of Financial Instruments - Schedule of Assets, Liabilities, and Equity Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds (included in cash and cash equivalents)	$ 22,930	$ 46,357
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Certificates of deposit (included in short-term investments)	1,504	1,749
Interest rate lock commitments	2	0
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Redeemable convertible preferred stock (mezzanine equity)	$ (791,106)	$ (655,416)