Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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-Publisher FASB
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-SubTopic 470
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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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Balance Type:	debit
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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-Topic 210
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-Section S99
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Debt and Credit Facility - Senior Secured Notes (Details) - USD ($)	9 Months Ended
	Dec. 31, 2019	Mar. 31, 2019	May 31, 2018
Debt Instrument [Line Items]
Debt issuance costs, net	$ 70,900,000	$ 83,600,000
Debt instrument, unamortized discount	$ 1,177,900,000	1,268,700,000
Senior Notes
Debt Instrument [Line Items]
Debt issuance costs, net			$ 24,400,000
Debt instrument, unamortized discount			10,500,000
Debt instrument, redemption price, percentage	101.00%
Senior Notes \| 2021 Senior Secured Notes
Debt Instrument [Line Items]
Debt instrument, face amount			$ 1,000,000,000.00
Debt instrument, interest rate, stated percentage	3.922%		3.922%
Debt issuance costs, net	$ 5,800,000	8,800,000
Debt instrument, unamortized discount	$ 2,600,000	3,800,000
Debt instrument, redemption price, percentage	100.00%
Senior Notes \| 2023 Senior Secured Notes
Debt Instrument [Line Items]
Debt instrument, face amount			$ 1,000,000,000.00
Debt instrument, interest rate, stated percentage	4.333%		4.333%
Debt issuance costs, net	$ 8,300,000	10,200,000
Debt instrument, unamortized discount	$ 3,700,000	$ 4,400,000
Senior Notes \| 2023 Senior Secured Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%
Senior Notes \| 2023 Senior Secured Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%