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Represents the maximum financing capacity under intra-entity transactions between entities under common control.

No definition available.

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Represents the principal amount of note to be issued by one entity to another entity under intra-entity transactions between entities under common control.

No definition available.

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Represents the period of intra-entity transactions between entities under common control.

No definition available.

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The net cash inflow or outflow due to the issuance or repayment of non-recourse funding obligations.

No definition available.

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Non-recourse funding obligations held by nonconsolidated affiliates.

No definition available.

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Non-recourse funding obligations issued by special purpose entities owned by the reporting entity and held by external parties. The funding obligations are direct financial obligations of the special purpose entity and are not guaranteed by the reporting entity.

No definition available.

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Total non-recourse funding obligations issued by special purpose entities owned by the reporting entity, including amounts held by affiliates and by external parties. The funding obligations are direct financial obligations of the special purpose entity and are not guaranteed by the reporting entity.

No definition available.

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Represents the year-to-date weighted-average interest rate of non-recourse funding obligations.

No definition available.

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Non-recourse funding obligations issued by special purpose entities owned by the reporting entity. The funding obligations are direct financial obligations of the special purpose entity and are not guaranteed by the reporting entity.

No definition available.

Name:	pl_NonrecourseFundingObligations
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Reinsurance Financing Agreement Capacity

No definition available.

Name:	pl_ReinsuranceFinancingAgreementCapacity
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Represents the outstanding nonrecourse funding obligations repurchased at discount.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The value of the collateral (typically cash) that the entity receives in a financing transaction in exchange for securities lent. This item represents a liability in the financial statements of the lender of the securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 25
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64840732&loc=d3e113275-111724

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Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Name:	us-gaap_DebtInstrumentFaceAmount
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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Name:	dei_LegalEntityAxis=pl_GoldenGateMember
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Data Type:	na
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Name:	dei_LegalEntityAxis=pl_GoldenGateIIMember
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Name:	dei_LegalEntityAxis=pl_RedMountainLLCMember
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Name:	dei_LegalEntityAxis=pl_GoldenGateVMember
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