Face (par) amount of debt instrument at time of issuance.

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Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Debt - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jul. 20, 2021
Standby Letters of Credit \| Subsequent Event
Debt Additional Information
Letters of Credit Outstanding, Amount		$ 0.0
Three-year Unsecured Revolving Credit Facility \| Subsequent Event
Debt Additional Information
Letters of Credit Outstanding, Amount		$ 0.0
4.125% Senior Notes due 2051 \| Senior Notes
Debt Additional Information
Debt Instrument, Face Amount	$ 600.0
Notes 4.500 Due 2025
Debt Additional Information
Debt Instrument, Repurchased Face Amount	500.0
Cost Related to Early Retirement of Debt	$ 67.3