Future Policy Benefits and Claims - Interest Accretion and Current Discount Rates (Details)	Sep. 30, 2023	Dec. 31, 2022
Retirement and Income Solutions \| Pension risk transfer
Future Policy Benefits and Claims
Interest accretion rate	4.45%	4.38%
Current discount rate	5.90%	5.31%
Retirement and Income Solutions \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.22%	4.22%
Current discount rate	5.89%	5.30%
Principal Asset Management \| Principal International \| Latin America \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.23%	4.24%
Current discount rate	3.82%	2.43%
Benefits and Protection \| Specialty Benefits \| Individual disability
Future Policy Benefits and Claims
Interest accretion rate	3.97%	4.03%
Current discount rate	5.95%	5.36%
Benefits and Protection \| Life Insurance \| Universal life
Future Policy Benefits and Claims
Interest accretion rate	4.76%	4.73%
Benefits and Protection \| Life Insurance \| Term life
Future Policy Benefits and Claims
Interest accretion rate	4.84%	4.89%
Current discount rate	5.86%	5.22%
Corporate \| Long-term care insurance
Future Policy Benefits and Claims
Interest accretion rate	6.16%	6.16%
Current discount rate	5.91%	5.34%

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Current weighted-average discount rate used to measure liability for future policy benefit.

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Original weighted-average discount rate at contract issue date used to measure liability for future policy benefit.

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