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10) Reinsurance, Commitments and Contingencies: Mortgage Loan Loss Settlements (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
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Amounts accrued for loan losses | $ 20,584,000 | $ 4,046,000

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- Definition Represents the monetary amount of Amounts accrued for loan losses, as of the indicated date. + References No definition available. + Details
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Namespace Prefix: | snfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- References No definition available. + Details
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Balance Type: | na
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