Represents the minimum number of days over which the entity's policy is to initiate foreclosure proceedings.

No definition available.

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- Definition

Represents the amount of financing receivables not subject to a pooling and servicing agreement that are nonperforming or have been restructured under the terms and conditions of the pooling and service agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The maximum number of days of accrued interest that can be carried on an impaired loan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Represents the average size of mortgage loans on real estate held in the portfolio on the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
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Balance Type:	debit
Period Type:	instant

- Definition

Represents the percentage of the mortgage loan portfolio represented by an single tenant.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the amount of mortgage loans on real estate due to the entity in the next fiscal year following the latest fiscal year ended, if the loans are called at their next call dates.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
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- Definition

Represents the amount of mortgage loans on real estate due to the entity in the seventh fiscal year through the eleventh fiscal year following the latest fiscal year, if the loans are called at their next call dates.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of mortgage loans on real estate due to the entity in the second fiscal year through the sixth fiscal year following the latest fiscal year, if the loans are called at their next call dates.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the amount of the largest mortgage loan on real estate held in the portfolio as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the loan-to-value ratio permitted on commercial mortgage loans in exchange for a participating interest in the cash flows from the underlying property.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the average size of new mortgage loans on real estate during the reporting period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Represents the amount of mortgage loans as of the balance sheet date which has a feature providing the entity a participating interest in the cash flows from the underlying real estate.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Represents the amount of income earned during the period on mortgage loans, which have a feature providing the entity a participating interest in the cash flows from the underlying real estate.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the period within which the call option or interest rate reset option on the mortgage loan on real estate can be exercised.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of single tenants whose exposure represents more then two percent of the mortgage loan portfolio.

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Troubled Debt Restructurings

+ References

No definition available.

+ Details

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Namespace Prefix:	plico_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents mortgage loans on real estate as a percentage of the total portfolio.

+ References

No definition available.

+ Details

Name:	plico_PercentageOfMortgageLoansOnRealEstate
Namespace Prefix:	plico_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column B
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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Namespace Prefix:	srt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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

- Definition

Amount of increase in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from new investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Footnote 6))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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

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MORTGAGE LOANS - Loan Portfolio and Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) restructuring reinsurer	Dec. 31, 2018 USD ($) restructuring	Dec. 31, 2017 USD ($) restructuring
Mortgage loans
Mortgage loans on real estate	$ 9,379,401	$ 7,724,733
Number of single tenants whose exposure represents more than 1.7% of mortgage loans \| reinsurer	0
Percentage of mortgage loans on real estate	100.00%	100.00%
Amount of new loans funded	$ 1,200,000
Average loan size of new loans funded	7,900
Average loan size of portfolio	$ 5,100
Weighted-average interest rate on mortgage loans (as a percent)	4.50%
Largest single mortgage loan	$ 78,000
Amount that would become due in 2020, if loans are called at their next call dates	134,000
Amount that would become due in 2021 through 2025, if loans are called at their next call dates	683,100
Amount that would become due in 2026 through 2029, if loans are called at their next call dates	$ 58,200
CALIFORNIA
Mortgage loans
Percentage of mortgage loans on real estate	11.90%	7.20%
TEXAS
Mortgage loans
Percentage of mortgage loans on real estate	7.70%	7.50%
ALABAMA
Mortgage loans
Percentage of mortgage loans on real estate	7.20%	8.60%
FLORIDA
Mortgage loans
Percentage of mortgage loans on real estate	6.50%	8.80%
GEORGIA
Mortgage loans
Percentage of mortgage loans on real estate	5.70%	7.30%
NORTH CAROLINA
Mortgage loans
Percentage of mortgage loans on real estate	5.00%	4.40%
UTAH
Mortgage loans
Percentage of mortgage loans on real estate	4.20%	4.70%
MICHIGAN
Mortgage loans
Percentage of mortgage loans on real estate	4.10%	4.80%
ILLINOIS
Mortgage loans
Percentage of mortgage loans on real estate	4.00%
OHIO
Mortgage loans
Percentage of mortgage loans on real estate	3.90%	4.50%
TENNESSEE
Mortgage loans
Percentage of mortgage loans on real estate		4.70%
All identified states
Mortgage loans
Percentage of mortgage loans on real estate	60.20%	62.50%
Retail
Mortgage loans
Percentage of mortgage loans on real estate	36.80%	45.00%
Office Buildings
Mortgage loans
Percentage of mortgage loans on real estate	14.40%	13.20%
Apartments
Mortgage loans
Percentage of mortgage loans on real estate	12.50%	10.20%
Warehouses
Mortgage loans
Percentage of mortgage loans on real estate	16.40%	11.30%
Senior housing
Mortgage loans
Percentage of mortgage loans on real estate	14.70%	15.80%
Other
Mortgage loans
Percentage of mortgage loans on real estate	5.20%	4.50%
Maximum
Mortgage loans
Single tenant's exposure as a percentage of mortgage loans	1.00%
Commercial mortgage loans
Mortgage loans
Mortgage loans having participation feature	$ 717,000	$ 700,600
Income recognized on participating mortgage loans	23,400	29,400	$ 37,200
Loans not subject to pooling and servicing agreement, non performing or restructured amount	$ 3,000	$ 3,000	$ 6,500
Number of troubled debt restructurings \| restructuring	4	1	2
Allowance for credit losses	$ 4,884	$ 1,296	$ 0
Maximum number of days accrued interest on impaired loans	90 days
Past due period at which to initiate foreclosure proceedings (more than)	90 days
Commercial mortgage loans \| Maximum
Mortgage loans
Period for exercise of call options or interest rate reset options	10 years
Loan-to-value ratio with participating interest (as a percent) (up to)	85.00%