v3.19.3

Debt (Narrative) (Details) - USD ($) | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018 | Mar. 31, 2019 | Feb. 11, 2019
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 4,750,000,000 |  | $ 4,300,000,000 |  |
Borrowings under long-term notes | 996,405,000 | $ 0 |  |  |
Payment for Debt Extinguishment or Debt Prepayment Cost | 8,270,000 | $ 0 |  |  |
Long term debt | 4,705,775,000 |  | 4,270,869,000 |  |
Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long term debt |  |  | $ 0 |  |
Commercial Paper [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 1,000,000,000.0 |  |  |  |
Long-term Debt, Weighted Average Interest Rate, over Time | 2.70% |  | 2.30% |  |
Commercial Paper [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Term | 397 days |  |  |  |
Three Point Nine Five Percentage Notes Due Two Thousand Fifty [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000.0 |  | $ 0 |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.95% |  |  |  |
Debt Instrument, Notes At Price | 99.91% |  |  |  |
Borrowings under long-term notes | $ 494,400,000 |  |  |  |
4.85% Notes Due 2049 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | 0 | $ 500,000,000.0 |
Debt Instrument, Interest Rate, Stated Percentage | 4.85% |  |  | 4.85% |
Debt Instrument, Notes At Price | 99.371% |  |  |  |
Borrowings under long-term notes | $ 491,500,000 |  |  |  |
Payment for Debt Extinguishment or Debt Prepayment Cost | 8,300,000 |  |  |  |
6.55% Notes due 2019 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 0 |  | 550,000,000 |  | $ 550,000,000.0
Debt Instrument, Interest Rate, Stated Percentage | 6.55% |  |  |  | 6.55%
Notes Payable to Banks [Member] | Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 500,000,000.0 |  |  |  |
Unused commitment fee | 0.10% |  |  |  |
Line of Credit Facility, Expiration Period | 364 days |  |  |  |
Short-term Debt | $ 0 |  |  |  |
Notes Payable to Banks [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Unused commitment fee | 0.075% |  |  |  |
Notes Payable to Banks [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Unused commitment fee | 0.125% |  |  |  |
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 |  |  |  |
Obligation for letters of credit | $ 3,500,000 |  | $ 6,800,000 |  |
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] | Notes Payable to Banks [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Notes Payable to Banks [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.25% |  |  |  |
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 remaining on line of credit facility before it terminates, 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=109500613&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=119400593&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=6876686&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=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
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- Definition The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
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