Statutory Financial Information, Capital Requirements, and Restrictions on Dividends and Transfers of Funds - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Statutory Accounting Practices [Line Items]
Retained earnings	$ 3,139,489	$ 3,029,396
Maximum Ordinary Dividends	$ 290,300
Maximum borrowing percentage	10.00%
New jersey dividend restriction percentage	10.00%
New york dividend restriction percentage	10.00%
New york dividend restriction on adjusted net investment income	100.00%
Parent Company
Statutory Accounting Practices [Line Items]
Retained earnings	$ 3,100,000
Additional borrowing capacity for parent	171,800
Parent Company
Statutory Accounting Practices [Line Items]
Investments and Cash	402,500
Retained earnings	$ 3,139,489	$ 3,029,396

The additional borrowing capacity for the Parent from the Indiana Subsidiaries.

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- Definition

Percentage used in New York's dividend restriction calculation.

+ References

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The maximum collaterized borrowing percentage from SISE and SISC admitted assets

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- Definition

Percentage used in New Jersey's dividend restriction calculation.

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Percentage used in New York's dividend restriction calculation.

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- Definition

Sum of investments and unrestricted cash as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section S99
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- Definition

Amount of accumulated undistributed earnings (deficit).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of dividends that can be declared or paid with approval of regulatory agency.

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