Long-Term Debt and Short-Term Borrowings - Long-Term Debt Maturities and Extinguishments (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Debt instrument
Commercial paper outstanding	$ 0	$ 0
Fixed rate medium term note due 2022
Debt instrument
Interest rate, stated percentage (as a percent)	2.75%
Loss on early debt extinguishment	$ 11,000,000
Debt redeemed	$ 450,000,000

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13)(2))
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(3))
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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 40
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