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New Accounting Guidance - Early Adoption (Details) - USD ($) $ in Millions | Mar. 31, 2018 | Jan. 01, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Disaggregation of Revenue [Line Items] |  |  |
Net receivables | $ 4,562 | $ 4,201 | $ 4,133
Other current assets | 540 | 542 | 224
Other assets | 1,535 | 1,656 | 1,430
Deferred tax assets | 554 | 552 | 669
Accounts payable and accrued liabilities | 2,343 | 2,205 | 2,083
Other liabilities | 1,267 | 1,334 | 1,311
Other Accumulated Comprehensive Income |  | (14) | 0
Retained earnings | 13,812 | 13,504 | $ 13,140
Accounting Standards Update 2014-09 |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Net receivables | 4,562 | 68 |
Other current assets | 540 | 318 |
Other assets |  | 226 |
Deferred tax assets | 554 | (103) |
Accounts payable and accrued liabilities | 2,343 | 122 |
Other liabilities | 1,267 | 23 |
Other Accumulated Comprehensive Income |  | 0 |
Retained earnings | $ 364 | 364 |
Accounting Standards Update 2016-01 |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Net receivables |  | 0 |
Other current assets |  | 0 |
Other assets |  | 0 |
Deferred tax assets |  | 0 |
Accounts payable and accrued liabilities |  | 0 |
Other liabilities |  | 0 |
Other Accumulated Comprehensive Income |  | (14) |
Retained earnings |  | 14 |
Accounting Standards Update 2016-16 |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Net receivables |  | 0 |
Other current assets |  | 0 |
Other assets |  | 0 |
Deferred tax assets |  | (14) |
Accounts payable and accrued liabilities |  | 0 |
Other liabilities |  | 0 |
Other Accumulated Comprehensive Income |  | 0 |
Cumulative effect of new accounting principle in period of adoption |  | $ (14) |

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