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Debt (Unsecured Fixed Rate Debt Securities Issued Under Current Shelf Registration) (Details) - USD ($) $ in Millions | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 10, 2021 | May 20, 2021
2.375% Notes Due 2031 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issuance date | May 20, 2021 |  |
Note amount |  |  | $ 850
Interest rate |  |  | 2.375%
Maturity date | May 20, 2031 |  |
3.200% Notes Due 2041 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issuance date | May 20, 2021 |  |
Note amount |  |  | $ 1,000
Interest rate |  |  | 3.20%
Maturity date | May 20, 2041 |  |
3.550% Notes Due 2061 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issuance date | May 20, 2021 |  |
Note amount |  |  | $ 650
Interest rate |  |  | 3.55%
Maturity date | May 20, 2061 |  |
2.375% Notes Due 2031 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issuance date | Sep. 10, 2021 |  |
Note amount |  | $ 150 |
Interest rate |  | 2.375% |
Maturity date | May 20, 2031 |  |
2.950% Notes Due 2052 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issuance date | Sep. 10, 2021 |  |
Note amount |  | $ 850 |
Interest rate |  | 2.95% |
Maturity date | Mar. 10, 2052 |  |

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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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