Stock Based Awards and Other Equity Instruments - Summary of RSU Activity, Including Service Based Awards and Performance-Based Awards (Parenthetical) (Details) - Restricted Stock Units - shares		1 Months Ended	3 Months Ended
		Nov. 30, 2017	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share transfer award	[1]		213,000
RSUs withheld to satisfy withholding tax requirements			269,878
CEO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share transfer award		213,000

[1] RSUs outstanding as of December 31, 2017 include 213,000 MSUs awarded to the Company’s CEO in November 2017. This award has been transferred to the MSU activity table below.