Fair Value Measurements Narrative (Details) - USD ($)	6 Months Ended	12 Months Ended
	Sep. 30, 2017	Mar. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Distributions paid	$ 0	$ 0
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-qualified deferred compensation asset	6,984,000	6,662,000
Non-qualified deferred compensation liability	4,128,000	$ 4,140,000
Deferred compensation liability, current	639,000
Other long term liabilities	$ 3,489,000