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Namespace Prefix:	pfg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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.

No definition available.

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of increase from purchase of financing receivable.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of decrease from sale and reclassification to held-for-sale of financing receivable.

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Name:	us-gaap_FinancingReceivableSignificantSales
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount, before allowance for credit loss, of financing receivable.

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