v3.20.2

Debt (Narrative) (Details) - USD ($) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Jun. 30, 2020 | Dec. 31, 2019
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Face Amount | $ 4,948,000,000 |  |  | $ 4,750,000,000
Borrowings under long-term notes | 499,400,000 | $ 996,405,000 |  |
Gain (Loss) on Extinguishment of Debt | (12,893,000) | $ (8,270,000) |  |
Commercial Paper [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Face Amount | 248,000,000 |  |  | 0
Line of Credit Facility, Maximum Borrowing Capacity | $ 1,000,000,000.0 |  |  |
Debt, Weighted Average Interest Rate | 0.60% |  |  |
Commercial Paper [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Term | 397 days |  |  |
3.25% Notes Due 2030 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | $ 500,000,000.0 | 0
Debt Instrument, Interest Rate, Stated Percentage | 3.25% |  | 3.25% |
Debt Instrument, Notes At Price, Percentage Of Par | 99.88% |  |  |
Borrowings under long-term notes | $ 495,200,000 |  |  |
4.25% Notes Due 2021 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Face Amount | $ 0 |  |  | 550,000,000
Debt Instrument, Interest Rate, Stated Percentage | 4.25% |  |  |
Extinguishment of Debt, Amount | $ 550,000,000 |  |  |
Gain (Loss) on Extinguishment of Debt | (12,900,000) |  |  |
Amortization of Debt Discount (Premium) | (700,000) |  |  |
Senior Notes [Member] | Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 1,000,000,000.0 |  |  |
Unused commitment fee | 0.125% |  |  |
Long term debt | $ 0 |  |  | 0
Obligation for letters of credit | $ 3,500,000 |  |  | $ 3,500,000
Senior Notes [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unused commitment fee | 0.075% |  |  |
Senior Notes [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unused commitment fee | 0.20% |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Senior Notes [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.875% |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Senior Notes [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.50% |  |  |

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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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