v3.19.1

Stock-Based Compensation (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Mar. 08, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Sale of Stock, Price Per Share |  |  |  | $ 15.25
Payments for Repurchase of Common Stock | $ 79,000,000 | $ 0 | $ 0 |
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost | 35,000,000 |  |  |
Stock-based compensation expense | 41,000,000 | 36,000,000 | 30,000,000 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value | 11,000,000 | 0 | 1,000,000 |
Option exercises | 0 | 0 | 1,000,000 |
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value | 88,000,000 | 23,000,000 | 17,000,000 |
Performance Shares [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share-based Liabilities Paid | 25,000,000 |  |  |
Share-based Compensation Arrangement by Liability Classified Share-based Payment Awards Accelerated Compensation Cost | 16,000,000 |  |  |
Allocated Share Based Compensation Expense Liability Classified Share-Based Awards | $ 16,000,000 | $ 6,000,000 | $ 1,000,000 |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Amount of cash paid related to share-based compensation liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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