Future Policy Benefits and Claims - Interest Accretion and Current Discount Rates (Details)	Mar. 31, 2024	Dec. 31, 2023
Retirement and Income Solutions \| Pension risk transfer
Future Policy Benefits and Claims
Interest accretion rate	4.54%	4.52%
Current discount rate	5.28%	4.99%
Retirement and Income Solutions \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.22%	4.22%
Current discount rate	5.26%	4.97%
Principal Asset Management \| Principal International \| Latin America \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.22%	4.22%
Current discount rate	3.41%	3.23%
Benefits and Protection \| Specialty Benefits \| Individual disability
Future Policy Benefits and Claims
Interest accretion rate	3.94%	3.96%
Current discount rate	5.33%	5.05%
Benefits and Protection \| Life Insurance \| Universal life
Future Policy Benefits and Claims
Interest accretion rate	4.75%	4.75%
Benefits and Protection \| Life Insurance \| Term life
Future Policy Benefits and Claims
Interest accretion rate	4.83%	4.83%
Current discount rate	5.19%	4.90%
Corporate \| Long-term care insurance
Future Policy Benefits and Claims
Interest accretion rate	6.16%	6.16%
Current discount rate	5.30%	5.01%

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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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