Debt - Non-Recourse Mortgages and Notes Payable (Details) - Mortgages and notes payable - Non-recourse - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Long-Term Debt
Real estate	$ 317.6	$ 198.3
Minimum
Long-Term Debt
Outstanding principal balances per real estate development	$ 3.0	$ 3.1
Interest rate (as a percent)	3.50%	3.50%
Maximum
Long-Term Debt
Outstanding principal balances per real estate development	$ 15.9	$ 14.4
Interest rate (as a percent)	4.80%	4.80%

Represents the outstanding principal balances of mortgages and other notes payable per real estate development.

No definition available.

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Namespace Prefix:	pfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Investments in real estate held for investment purposes and held-for-sale.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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