Employee and Agent Benefits - Plan Information (Details)	12 Months Ended
Dec. 31, 2020
Pension benefits
Defined Benefit Plan Disclosures
Period of employment used to calculate average annual compensation for the final average pay benefit	5 years

The final average pay benefit is based on the years of service and generally the employee's or agent's average annual compensation during the most recent years of employment for this time period.

No definition available.

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Period Type:	duration