Intangible Assets - Gross Carrying Amount and Accumulated Amortization of Other Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 81,021	$ 78,989	$ 61,807
Accumulated Amortization	24,527	21,960	19,609
Tradenames and trademarks
Acquired Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	24,353	24,353	19,953
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	48,657	48,657	39,757
Accumulated Amortization	21,968	19,976	18,050
Favorable lease contracts
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,882	3,882	0
Accumulated Amortization	657	299	0
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,435	403	403
Accumulated Amortization	499	393	378
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,164	1,164	1,164
Accumulated Amortization	999	941	883
Non-compete
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	530	530	530
Accumulated Amortization	$ 404	$ 351	$ 298