Separate Account Balances - Principal Asset Management - International Pension (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Changes in separate account liabilities
Balance at beginning of period	$ 173,327.1
Balance at end of period	180,728.0	$ 173,327.1
Principal Asset Management \| International Pension \| Pension \| Latin America
Changes in separate account liabilities
Balance at beginning of period	32,802.2	34,580.6
Premiums and deposits	1,656.3	3,347.7
Policy charges	(8.6)	(16.6)
Surrenders, withdrawals and benefit payments	(1,934.8)	(3,638.0)
Investment performance	2,262.8	2,890.1
Other	(24.8)	22.8
Foreign currency translation adjustment	2,197.2	(4,384.4)
Balance at end of period	36,950.3	32,802.2
Cash surrender value	$ 36,950.3	$ 32,802.2

Amount increase (decrease) in separate account liability from foreign currency translation.

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- Definition

Amount of decrease in separate account liability from contract redemption and withdrawal of funds and cash outflow to separate account policyholder from benefit payment.

+ References

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- Definition

Amount of separate account liability payable to policyholder upon surrender of contract before maturity.

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- Definition

Amount of increase (decrease) in separate account liability from performance of investment.

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Amount increase (decrease) in separate account liability from change, classified as other.

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Amount of decrease in separate account liability from policy charge.

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- Definition

Amount of cash inflow to separate account liability from premium and deposit from cash received.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of liability for variable contract in which all or portion of contract holder's funds is allocated to specific separate account and supported by assets held in separate account.

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