Share-Based Compensation - Unvested RSAs Outstanding (Details) - RSAs	6 Months Ended
	Jun. 30, 2017 $ / shares shares
Number of Shares
Unvested RSAs, Beginning Balance (in shares) | shares	328,347
Granted (in shares) | shares	7,445
Vested (in shares) | shares	(81,397)
Forfeited (in shares) | shares	(4,020)
Unvested RSAs, Ending Balance (in shares) | shares	250,375
Weighted-Average Grant Date Fair Value
Unvested RSAs, Beginning Balance (in dollars per share) | $ / shares	$ 22.87
Granted (in dollars per share) | $ / shares	39.77
Vested (in dollars per share) | $ / shares	20.46
Forfeited (in dollars per share) | $ / shares	23.09
Unvested RSAs, Ending Balance (in dollars per share) | $ / shares	$ 24.15