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Summary of Significant Accounting Principles and Practices - Schedule of Changes to Balance Sheet for New Accounting Standards (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Jan. 01, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Assets |  |  |
Operating lease right-of-use assets | $ 929 |  |
Other non-current assets | 570 |  | $ 448
Liabilities |  |  |
Other current liabilities | 1,086 |  | 936
Non-current operating lease liabilities | 944 |  |
Other non-current liabilities | $ 877 |  | 1,097
Operating Lease Right Of Use Assets |  |  |
Assets |  |  |
Operating lease right-of-use assets |  | $ 1,021 |
Other Noncurrent Assets |  |  |
Assets |  |  |
Other non-current assets |  | 526 | 448
Other Current Liabilities |  |  |
Liabilities |  |  |
Other current liabilities |  | 1,155 | 936
Other Noncurrent Operating Lease Liabilities |  |  |
Liabilities |  |  |
Non-current operating lease liabilities |  | 1,014 |
Other Noncurrent Liabilities |  |  |
Liabilities |  |  |
Other non-current liabilities |  | 963 | $ 1,097
Accounting Standards Update 2016-02 |  |  |
Assets |  |  |
Operating lease right-of-use assets |  | 1,100 |
Accounting Standards Update 2016-02 | Operating Lease Right Of Use Assets |  |  |
Assets |  |  |
Operating lease right-of-use assets |  | 1,021 |
Accounting Standards Update 2016-02 | Other Noncurrent Assets |  |  |
Assets |  |  |
Other non-current assets |  | 78 |
Accounting Standards Update 2016-02 | Other Current Liabilities |  |  |
Liabilities |  |  |
Other current liabilities |  | 219 |
Accounting Standards Update 2016-02 | Other Noncurrent Operating Lease Liabilities |  |  |
Liabilities |  |  |
Non-current operating lease liabilities |  | 1,014 |
Accounting Standards Update 2016-02 | Other Noncurrent Liabilities |  |  |
Liabilities |  |  |
Other non-current liabilities |  | $ (134) |

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