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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Topic 835
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- Definition

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

+ References

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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.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 835
-SubTopic 30
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Debt and Credit Facility Senior Secured Notes (Details) - USD ($)	3 Months Ended
	Jun. 30, 2018	May 31, 2018	Mar. 31, 2018	Feb. 28, 2017
Debt Instrument [Line Items]
Debt issuance costs	$ 110,000,000	$ 24,400,000	$ 40,100,000	$ 33,700,000
Debt Instrument, Unamortized Discount	$ 1,355,700,000	10,500,000	1,372,900,000
2021 Notes
Debt Instrument [Line Items]
Principal amount		$ 1,000,000,000.00
Coupon Interest Rate	3.922%	3.922%
Debt issuance costs	$ 11,800,000		0
Debt Instrument, Unamortized Discount	$ 5,100,000		0
Effective Interest Rate		3.922%
Debt Instrument, redemption price, percentage	100.00%
2023 Notes
Debt Instrument [Line Items]
Principal amount		$ 1,000,000,000.00
Coupon Interest Rate	4.333%	4.333%
Debt issuance costs	$ 12,000,000		0
Debt Instrument, Unamortized Discount	$ 5,200,000		$ 0
Effective Interest Rate		4.333%
2023 Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt Instrument, redemption price, percentage	100.00%
2023 Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt Instrument, redemption price, percentage	100.00%
Change of Control Triggering Event \| Senior Secured Notes
Debt Instrument [Line Items]
Debt Instrument, redemption price, percentage	101.00%