Related Parties (Details) - EBP 002 - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments, at fair value	$ 2,378,392	$ 2,122,600
Dividends and interest	40,650
Payment of maintenance fees	$ 875
Cash dividends, vesting percentage	100.00%
Investment, number of common stock (in shares)
Dividend income on investment	$ 702
Maximum
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Maximum common stock to total asset, percentage	25.00%
Collective investment trusts
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investment, number of common stock (in shares)
Collective investment trusts \| Trustee
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments, at fair value	$ 1,855,600	$ 1,619,900
Concentration of investment at fair value to net assets, percentage	78.00%	76.00%
Dividends and interest	$ 21,000
Realized gains (losses) from investments	65,600
Unrealized gains (losses) from investments	181,900
Collective investment trusts \| Custodian
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments, at fair value	226	$ 228
Assurant, Inc. common stock
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments, at fair value	$ 50,100	$ 47,200
Investment, number of common stock (in shares)	208,201	221,470

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EBP, Investment, Cash Dividends, Vesting Percentage

+ References

No definition available.

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Percentage of investment at fair value held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), to net assets available for benefit representing concentration risk at or above applicable threshold.

+ References

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Amount of increase (decrease) in net asset available for benefit from realized gain (loss) on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Percentage of investment in common stock of employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), to total plan assets.

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Number of shares or units of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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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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