Debt Instrument, Amount To Be Amended, Redeemed Or Refinanced To Avoid Acceleration

No definition available.

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- Definition

Increase in percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM format.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Period Type:	instant

- 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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

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+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
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-Publisher FASB
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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Debt (Components of Debt) (Details) - USD ($) $ in Millions		1 Months Ended			3 Months Ended	12 Months Ended
Debt (Components of Debt) (Details) - USD ($) $ in Millions	Apr. 26, 2018	Sep. 30, 2017	Jul. 31, 2016	Jan. 31, 2015	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 4,433	$ 4,433
Unamortized Issuance Expense					(38)	(40)
Unamortized Debt Discount					(2)	(2)
Total					4,393	4,391
Long-term Debt [Member] \| 2016 Term Loan due December 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument					1,191	1,191		$ 1,191
Unamortized Issuance Expense					(8)	(8)
Total					$ 1,183	$ 1,183
Variable interest rate					4.24%	3.98%
Maturity date, year and month					2020-12	2020-12
Long-term Debt [Member] \| 4.05% Senior Notes due January 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 92	$ 92
Total					$ 92	$ 92
Stated interest rate			5.80%	4.05%	4.05%	4.05%
Maturity date, year and month				2020-01	2020-01	2020-01
Repayments of long-term debt		$ 758
Long-term Debt [Member] \| 4.05% Senior Notes due January 2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate							6.05%
Long-term Debt [Member] \| 4.10% Senior Notes due March 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 1,000	$ 1,000
Unamortized Issuance Expense					(6)	(7)
Total					$ 994	$ 993
Stated interest rate					4.10%	4.10%
Maturity date, year and month					2022-03	2022-03
Long-term Debt [Member] \| 4.95% Senior Notes due January 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 1,000	$ 1,000
Unamortized Issuance Expense					(8)	(8)
Unamortized Debt Discount					(2)	(2)
Total					$ 990	$ 990
Stated interest rate			6.70%	4.95%	4.95%	4.95%
Maturity date, year and month				2025-01	2025-01	2025-01
Long-term Debt [Member] \| 4.95% Senior Notes due January 2025 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate							6.95%
Long-term Debt [Member] \| 7.50% Senior Notes due April 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 650	$ 650
Unamortized Issuance Expense					(9)	(10)
Total					$ 641	$ 640
Stated interest rate		7.50%			7.50%	7.50%
Maturity date, year and month		2026-04			2026-04	2026-04
Long-term Debt [Member] \| 7.75% Senior Notes due October 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument					$ 500	$ 500
Unamortized Issuance Expense					(7)	(7)
Total					$ 493	$ 493
Stated interest rate		7.75%			7.75%	7.75%
Maturity date, year and month		2027-10			2027-10	2027-10
Senior Notes [Member]
Debt Instrument [Line Items]
Increase in basis spread			1.75%
Subsequent Event [Member] \| 2018 Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount borrowed	$ 360
Subsequent Event [Member] \| Long-term Debt [Member] \| 2018 Credit Facility [Member]
Debt Instrument [Line Items]
Amount to be amended, redeemed or refinanced to avoid acceleration	700
Line of credit, amount borrowed	360
Subsequent Event [Member] \| Long-term Debt [Member] \| 2016 Term Loan due December 2020 [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 1,191
Over LIBOR [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Increase in basis spread			1.75%