Long-term Debt - Schedule of Carrying Amounts and Estimated Fair Values of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Mar. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 2,021,807	$ 1,807,507
Reported Value Measurement [Member]
Debt Instrument [Line Items]
Long-term debt	2,021,807	1,807,507
Estimate of Fair Value Measurement [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,787,557	$ 1,559,455

Amount of short-term and long-term debt and lease obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Name:	us-gaap_DebtAndCapitalLeaseObligations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant