Interest Rate Cap Agreements (Schedule of Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Mar. 31, 2020
Derivatives Fair Value [Line Items]
Prepaid expenses and other current assets	$ 125,996	$ 117,967
Accrued expenses	(452,974)	(390,294)
Other long-term liabilities	(76,807)	(93,487)
Fair Values of Derivative Instruments Asset (Liability) Derivatives	(40,314)
Designated as Hedging Instrument [Member] \| Interest Rate Cap Agreements [Member]
Derivatives Fair Value [Line Items]
Prepaid expenses and other current assets
Accrued expenses	(28,961)	(28,131)
Other long-term liabilities	(10,374)	(19,277)
Fair Values of Derivative Instruments Asset (Liability) Derivatives	$ (39,335)	$ (47,408)

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

+ References

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(7))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Topic 210
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6676-107765

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-Name Accounting Standards Codification
-Topic 210
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