Share-based Compensation - Assumptions used and Rollforward (Details) - Stock options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended		12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Weighted average assumptions used to estimate fair values of the stock options granted and the estimated annual forfeiture rates used to recognize the associated compensation expense and the weighted average fair value of the options granted
Risk-free interest rate (as a percent)	1.10%	1.70%
Expected volatility (as a percent)	55.60%	48.30%
Expected dividend yield (as a percent)	0.00%	0.00%
Forfeiture rate (as a percent)	6.50%	6.50%
Expected term (in years)	5 years 2 months 12 days	5 years 2 months 12 days
Weighted average fair value (in dollars per share)	$ 15.33	$ 26.24
Awards
Outstanding at the beginning of the period (in shares)	1,730
Granted (in shares)	11
Exercised (in shares)	(190)
Forfeited, expired or repurchased (in shares)	(19)
Outstanding at the end of the period (in shares)	1,532		1,730
Vested and expected to vest, Awards (in shares)	1,525
Exercisable at end of year (in shares)	1,379
Stock options, Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 16.77
Granted (in dollars per share)	31.30
Exercised (in dollars per share)	6.54
Forfeited, expired or repurchased (in dollars per share)	31.40
Outstanding at the end of the period (in dollars per share)	17.96		$ 16.77
Vested and expected to vest, Weighted-Average Exercise Price (in dollars per share)	17.85
Exercisable at the end of the period (in dollars per share)	$ 15.64
Aggregate Intrinsic Value
Outstanding at the beginning of the period (in dollars)	$ 19,524
Exercised (in dollars)	4,325
Outstanding at the end of the period (in dollars)	14,370		$ 19,524
Vested and expected to vest, Aggregate Intrinsic Value	14,370
Exercisable at the end of the period (in dollars)	$ 14,370
Weighted Average Remaining Contractual Life (yrs.)
Outstanding at the end of the period (in years)	6 years 2 months 12 days		6 years 3 months 18 days
Vested and expected to vest, Weighted Average Remaining Contractual Life	6 years 2 months 12 days
Exercisable at the end of the period (in years)	6 years