Sale of Receivables (Details)	6 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($) program	Sep. 30, 2015 USD ($)	Mar. 31, 2016 USD ($)	Apr. 01, 2016 USD ($)
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets [Line Items]
Number of accounts receivable securitization programs | program	2
Receivables sold, face value discounted, percentage	100.00%
Reductions of trade and other receivables due to settlements	$ 1,531,000	$ 4,170,000	$ 9,113,000
Receivables outstanding in facility	95,030,000	101,723,000	188,764,000
Beneficial interest	29,371,000	21,792,000	40,368,000
Servicing liability	0	29,000	58,000
Cash purchase price	246,235,000	201,161,000	585,648,000
Deferred purchase price	113,509,000	81,181,000	233,753,000
Service fees	286,000	298,000	553,000
Total	360,030,000	$ 282,640,000	819,954,000
Accounts Receivable Securitization, Program One
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets [Line Items]
Trade receivables sold, maximum amount	$ 100,000			$ 150,000
Service fee percentage	0.50%
Accounts Receivable Securitization, Program Two
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets [Line Items]
Trade receivables sold, maximum amount	$ 35,000,000
Asset Backed Securities Programs Number Three
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets [Line Items]
Trade receivables sold, maximum amount			$ 100,000,000