Accounting Pronouncements (Details) - USD ($) $ in Millions |
Jun. 30, 2019 |
Mar. 31, 2019 |
---|---|---|
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Operating lease assets (Note 16) | $ 2,076 | |
Operating lease liabilities (Note 16) | $ 1,612 | |
Minimum [Member] | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Finance lease, renewal term | 12 months | |
Operating lease, renewal term | 12 months | |
ASU 2016-02 Adopted [Member] | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Operating lease assets (Note 16) | $ 2,000 | |
Operating lease liabilities (Note 16) | $ 2,000 | |
ASU 2016-02 Adopted [Member] | Minimum [Member] | ||
New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
Finance lease, renewal term | 12 months | |
Operating lease, renewal term | 12 months |