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Debt - Senior Notes and Junior Subordinated Notes (Details) - 4.200% Junior Subordinated Notes due 2061 - Junior subordinated notes - Subsequent Event	Jul. 13, 2021 USD ($)
Debt Instrument [Line Items]
Face amount	$ 200,000,000.0
Debt interest rate	4.20%
Issuance price, percentage of principal amount	1
On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
If a rating agency makes certain changes relating to the equity credit criteria for securities
Debt Instrument [Line Items]
Redemption price percentage	102.00%

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