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Subsequent Event (Details) - USD ($)	Nov. 01, 2021	Oct. 29, 2021	Jun. 18, 2019
Subsequent Event [Line Items]
Number of shares authorized to be repurchased			100,000,000
Subsequent Event
Subsequent Event [Line Items]
Accelerated share repurchase payment		$ 316,000,000
Subsequent Event \| Parent Company \| Senior Notes \| Fixed Rate/Floating Rate Senior Notes Due November 1, 2027
Subsequent Event [Line Items]
Principal amount	$ 500,000,000
Subsequent Event \| Parent Company \| Senior Notes \| Fixed Rate/Floating Rate Senior Notes Due November 1, 2027 \| One year prior to maturity date
Subsequent Event [Line Items]
Redemption price percentage	100.00%
Subsequent Event \| Parent Company \| Senior Notes \| Fixed Rate/Floating Rate Senior Notes Due November 1, 2027 \| 30 days prior to maturity date
Subsequent Event [Line Items]
Redemption price percentage	100.00%
Subsequent Event \| Parent Company \| Senior Notes \| Fixed Rate 1.707% Senior Notes
Subsequent Event [Line Items]
Interest rate	1.707%
Subsequent Event \| Parent Company \| Senior Notes \| Senior Notes with Compounded SOFR Interest Rate \| SOFR
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	0.685%
Subsequent Event \| Parent Company \| Senior Notes \| Senior Notes with Floating Interest Rate \| LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	0.57%