Summary of Unpaid Principal Balances of the Servicing Portfolio (Details) - USD ($)	Mar. 31, 2026	Dec. 31, 2025
Intangible Asset, Goodwill and Other [Abstract]
Servicing unpaid principal balance	$ 358,018,607	$ 361,632,543

Represents the monetary amount of Servicing Unpaid Principal Balance, as of the indicated date.

No definition available.

Name:	SNFCA_ServicingUnpaidPrincipalBalance
Namespace Prefix:	SNFCA_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant