Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	2 Months Ended	12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
RSL and RSI | RSL and RSI | Services Agreement
Related Party Transaction [Line Items]
Base salary, fringe benefits, and share-based compensation		$ 0.4	$ 7.7	$ 9.2
RSL | RSL | Share-Based Compensation Allocated to the Company by RSL
Related Party Transaction [Line Items]
Base salary, fringe benefits, and share-based compensation		$ 1.0	$ 1.0	$ 4.9
RSL | RSL | Option Agreement
Related Party Transaction [Line Items]
Option agreement, term	2 years
Option agreement, purchase price as a percent of payments made by RSL	110.00%