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Fair Value Measurements (Details 1) - USD ($) $ in Millions | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Instrument [Line Items] |  |
Notes payable, carrying value | $ 5,961.7 | $ 5,954.8
Debt instruments, fair value | 6,681.3 | 6,553.6
2.900% Senior Notes due 2020 |  |
Debt Instrument [Line Items] |  |
Notes payable, fair value | 1,498.1 | 1,509.6
Notes payable, carrying value | 1,501.8 | 1,495.8
3.625% Senior Notes due 2022 |  |
Debt Instrument [Line Items] |  |
Notes payable, fair value | 1,022.0 | 1,038.9
Notes payable, carrying value | 996.9 | 996.6
4.050% Senior Notes due 2025 |  |
Debt Instrument [Line Items] |  |
Notes payable, fair value | 1,838.1 | 1,897.2
Notes payable, carrying value | 1,739.9 | 1,739.5
5.200% Senior Notes due 2045 |  |
Debt Instrument [Line Items] |  |
Notes payable, fair value | 2,323.1 | 2,107.9
Notes payable, carrying value | $ 1,723.1 | $ 1,722.9

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- Definition Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer. + References Reference 1: 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 2: 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 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 + Details
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