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Discontinued Operations - Income Statement (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Expenses |  |  |  |  |  |  |  |  |  |  |
Net income (loss) from discontinued operations | $ 0 | $ (1) | $ 0 | $ 0 | $ 69 | $ (2) | $ 1 | $ 6 | $ (1) | $ 74 | $ 828
Tempo Business | Discontinued Operations |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  |  |  |
Total revenue |  |  |  |  |  |  |  |  | 0 | 0 | 698
Expenses |  |  |  |  |  |  |  |  |  |  |
Total operating expenses |  |  |  |  |  |  |  |  | 2 | 12 | 656
Operating income from discontinued operations |  |  |  |  |  |  |  |  | (2) | (12) | 42
Other income |  |  |  |  |  |  |  |  | 0 | 0 | 10
Income (loss) from discontinued operations before income taxes |  |  |  |  |  |  |  |  | (2) | (12) | 52
Income tax expense (benefit) |  |  |  |  |  |  |  |  | (1) | (4) | 3
Net income (loss) from discontinued operations, excluding gain |  |  |  |  |  |  |  |  | (1) | (8) | 49
Gain on sale of discontinued operations, net of tax |  |  |  |  |  |  |  |  | 0 | 82 | 779
Net income (loss) from discontinued operations |  |  |  |  |  |  |  |  | $ (1) | $ 74 | $ 828

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- Definition Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e957-107759 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3B -URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721525-107759 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5C -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760 + Details
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