Long-Term Debt - Narrative (Details) - Line of Credit	1 Months Ended	3 Months Ended
Mar. 31, 2026 USD ($)	Mar. 31, 2026 USD ($)
Revolving credit facility
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Maximum borrowing capacity	$ 1,000,000,000.0	$ 1,000,000,000.0
Accordion feature, higher borrowing capacity option	$ 500,000,000	$ 500,000,000
Consolidated net worth percentage	70.00%	70.00%
Net worth percentage, increase adjustment from equity issuances	50.00%	50.00%
Ratio of indebtedness to net capital	0.35	0.35
Letter of credit
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Maximum borrowing capacity	$ 500,000,000	$ 500,000,000
Uncommitted Money Market Line Credit Agreement
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Maximum borrowing capacity	500,000,000	500,000,000
Minimum cash advance request	100,000	100,000
Senior Notes 2036 And 2056 \| Unsecured Debt
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Stockholders' equity threshold triggering required facility exercise	2,800,000,000	2,800,000,000
Origination costs	$ 7,000,000	$ 7,000,000
2036 Senior Notes \| Unsecured Debt
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Debt instrument, term	10 years	10 years
Pre-capitalized securities, sold by trust	$ 500,000,000
Debt maximum issuable amount	$ 500,000,000	$ 500,000,000
Stated interest rate	6.311%	6.311%
Fee percentage	2.066%
2056 Senior Notes \| Unsecured Debt
Schedule of Long Term and Short Term Debt Instruments [Line Items]
Debt instrument, term	30 years	30 years
Pre-capitalized securities, sold by trust	$ 400,000,000
Debt maximum issuable amount	$ 400,000,000	$ 400,000,000
Stated interest rate	7.28%	7.28%
Fee percentage	2.43%

Debt Instrument, Consolidated Net Worth Percentage

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Debt Instrument, Consolidated Net Worth Percentage, Increase Adjustment From Equity Issuances

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- Definition

Debt Instrument, Fee Percentage

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- Definition

Debt Instrument, Maximum Issuable Amount

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- Definition

Debt Instrument, Threshold, Stockholders’ Equity Trigger

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- Definition

Line Of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

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- Definition

Line Of Credit Facility, Minimum Cash Advance Request

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- Definition

Pre-Capitalized Securities, Sold By Trust

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Schedule of Long Term and Short Term Debt Instruments

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-1A

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Indebtedness divided by net capital.

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