Debt - Narrative (Details) - USD ($)		12 Months Ended
	Sep. 15, 2023	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021		Jul. 12, 2021	Jul. 11, 2021
Debt Instrument [Line Items]
Principal repayment on Revolving Credit Facility		$ 249,000,000.0	$ 0		$ 0
Principal borrowings on Revolving Credit Facility		$ 0	$ 0	[1]	$ 114,000,000.0	[1]
Purchase of FHLB activity-based common stock as percentage of borrowing, percentage, authorized		15.00%	25.00%
Senior Notes
Debt Instrument [Line Items]
Principal amount		$ 250,000,000
Stated rate		4.50%
Effective interest percentage		4.53%
Senior Notes | 2023 Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 300,000,000	$ 300,000,000.0	$ 300,000,000.0
Stated rate	7.25%	7.25%
Effective interest percentage	7.29%
Debt redemption price, percentage	100.00%
Debt redemption price, interest discounted at treasury yield margin	0.45%
Line of Credit
Debt Instrument [Line Items]
Borrowing capacity							$ 325,000,000	$ 225,000,000
Commitment fee percent		0.15%
Line of Credit | SOFR
Debt Instrument [Line Items]
Basis spread on variable rate		1.15%
Revolving Credit Facility
Debt Instrument [Line Items]
Principal repayment on Revolving Credit Facility	$ 249,000,000
Principal borrowings on Revolving Credit Facility		$ 114,000,000

[1] Recast for the adoption of ASU 2018-12. See Note 1 of the Consolidated Financial Statements