Name:	plic_CashCollateralReceivedAssociatedWithDerivatives
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The carrying value as of the balance sheet date of the cash and securities pledged as collateral associated with derivative credit support agreements and Futures Commission Merchant agreements.

No definition available.

Name:	plic_DerivativeCollateralPledged
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Data Type:	xbrli:monetaryItemType
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The carrying value as of the balance sheet date of the cash and securities received as collateral associated with derivative credit support agreements.

No definition available.

Name:	plic_DerivativeCollateralReceived
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The amount at risk if a counterparty to the derivative instruments does not perform.

No definition available.

Name:	plic_DerivativeCreditExposure
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount at risk if a counterparty to the derivative instrument does not perform, after considering collateral received.

No definition available.

Name:	plic_DerivativeNetCreditExposure
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Data Type:	xbrli:monetaryItemType
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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:	plic_DerivativeNotionalCreditExposureLineItems
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Represents the amount of cash exchanged under the interest rate derivative contracts.

No definition available.

Name:	plic_InterestRateDerivativesCashExchanged
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Represents the amount of principal payments made by parties to the interest rate derivative contracts.

No definition available.

Name:	plic_InterestRateDerivativesPrincipalPayments
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Data Type:	xbrli:monetaryItemType
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The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeForwardMember
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