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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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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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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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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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

Name:	us-gaap_AdditionalCollateralAggregateFairValue
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

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Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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