Future Policy Benefits and Claims - Interest Accretion and Current Discount Rates (Details)	Jun. 30, 2026	Dec. 31, 2025
Retirement and Income Solutions \| Pension risk transfer
Future Policy Benefits and Claims
Interest accretion rate	4.72%	4.70%
Current discount rate	5.49%	5.28%
Retirement and Income Solutions \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.22%	4.22%
Current discount rate	5.41%	5.16%
Principal Asset Management \| International Pension \| Latin America \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.19%	4.19%
Current discount rate	3.10%	2.78%
Benefits and Protection \| Specialty Benefits \| Individual disability
Future Policy Benefits and Claims
Interest accretion rate	3.82%	3.84%
Current discount rate	5.62%	5.43%
Benefits and Protection \| Life Insurance \| Universal life
Future Policy Benefits and Claims
Interest accretion rate	4.74%	4.74%
Benefits and Protection \| Life Insurance \| Term life
Future Policy Benefits and Claims
Interest accretion rate	4.67%	4.81%
Current discount rate	5.21%	4.91%
Corporate \| Long-term care insurance
Future Policy Benefits and Claims
Interest accretion rate	6.16%	6.16%
Current discount rate	5.56%	5.36%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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