Securitized Receivables - Narrative (Details)	6 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) program	Sep. 30, 2018 USD ($)	Mar. 31, 2019 USD ($)
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of accounts receivable securitization programs | program	2
Receivables sold, face value discounted (as a percent)	100.00%
Reductions of trade and other receivables due to settlements	$ (12,446,000)	$ (5,328,000)	$ (5,208,000)
Accounts Receivable Securitization, Program Two
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Trade receivables, maximum amount	$ 125,000,000