v3.19.1

Debt Senior Unsecured Notes (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Mar. 31, 2015 | Sep. 30, 2014
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term Debt |  | $ 10,156 | $ 11,213 |  |  |
Debt Issuance Costs, Net |  | 112 |  |  |  |
Gains (Losses) on Extinguishment of Debt |  | 28 | (38) | $ (25) |  |
Senior Unsecured Notes 2023 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term Debt |  | $ 1,227 | $ 1,239 |  |  |
Debt Instrument, Interest Rate, Effective Percentage | [1] | 5.60% | 5.60% |  |  |
Debt Instrument, Face Amount |  |  |  |  |  | $ 1,250
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  | 5.375%
Gains (Losses) on Extinguishment of Debt |  | $ 1 |  |  |  |
Senior Unsecured Notes 2024 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term Debt |  | $ 599 | $ 644 |  |  |
Debt Instrument, Interest Rate, Effective Percentage | [1] | 5.70% | 5.70% |  |  |
Debt Instrument, Face Amount |  |  |  |  | $ 650 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  | 5.50% |
Gains (Losses) on Extinguishment of Debt |  | $ 4 |  |  |  |
Senior Unsecured Notes 2025 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term Debt |  | $ 1,210 | $ 1,534 |  |  |
Debt Instrument, Interest Rate, Effective Percentage | [1] | 6.00% | 6.00% |  |  |
Debt Instrument, Face Amount |  |  |  |  |  | $ 1,550
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  | 5.75%
Gains (Losses) on Extinguishment of Debt |  | $ 30 |  |  |  |
Unsecured Debt [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term Debt |  | 3,036 | $ 3,417 |  |  |
Gains (Losses) on Extinguishment of Debt |  | $ 35 |  |  |  |
[1] | Our weighted average interest rate calculation includes the amortization of debt issuance costs.

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 + Details
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- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 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(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: 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(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: 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(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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