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Debt - Schedule of Principal Terms of Senior and Junior Subordinated Notes (Details) | 6 Months Ended
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Jun. 30, 2021 USD ($)
Senior notes | 2024 Senior Notes |
Debt Instrument [Line Items] |
Par value | $ 400,000,000.0
Stated coupon | 4.25%
Redemption price percentage | 100.00%
Senior notes | 2024 Senior Notes | Treasury Rate |
Debt Instrument [Line Items] |
Applicable basis spread over redemption price percentage | 0.25%
Senior notes | 2025 Senior Notes |
Debt Instrument [Line Items] |
Par value | $ 350,000,000.0
Stated coupon | 3.50%
Redemption price percentage | 100.00%
Senior notes | 2025 Senior Notes | Treasury Rate |
Debt Instrument [Line Items] |
Applicable basis spread over redemption price percentage | 0.25%
Senior notes | 2030 Senior Notes |
Debt Instrument [Line Items] |
Par value | $ 350,000,000.0
Stated coupon | 3.30%
Redemption price percentage | 100.00%
Senior notes | 2030 Senior Notes | Treasury Rate |
Debt Instrument [Line Items] |
Applicable basis spread over redemption price percentage | 0.40%
Junior subordinated notes | 2059 Junior Subordinated Notes |
Debt Instrument [Line Items] |
Par value | $ 300,000,000.0
Stated coupon | 5.875%
Junior subordinated notes | 2059 Junior Subordinated Notes | On or after March 30. 2024 (after September 30, 2025 - 2060 Junior Subordinated Notes) |
Debt Instrument [Line Items] |
Redemption price percentage | 100.00%
Junior subordinated notes | 2059 Junior Subordinated Notes | If changes in tax laws and interpretations occur |
Debt Instrument [Line Items] |
Redemption price percentage | 100.00%
Junior subordinated notes | 2059 Junior Subordinated Notes | If a rating agency makes certain changes relating to the equity credit criteria for securities |
Debt Instrument [Line Items] |
Redemption price percentage | 102.00%
Junior subordinated notes | 2060 Junior Subordinated Notes |
Debt Instrument [Line Items] |
Par value | $ 275,000,000.0
Stated coupon | 4.75%
Junior subordinated notes | 2060 Junior Subordinated Notes | On or after March 30. 2024 (after September 30, 2025 - 2060 Junior Subordinated Notes) |
Debt Instrument [Line Items] |
Redemption price percentage | 100.00%
Junior subordinated notes | 2060 Junior Subordinated Notes | If changes in tax laws and interpretations occur |
Debt Instrument [Line Items] |
Redemption price percentage | 100.00%
Junior subordinated notes | 2060 Junior Subordinated Notes | 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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