SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Protective Life Insurance Company (the “Company”), a stock life insurance company, was founded in 1907. The Company is a wholly owned subsidiary of Protective Life Corporation (“PLC”), an insurance holding company. On February 1, 2015, PLC became a wholly owned subsidiary of The Dai-ichi Life Insurance Company, Limited, a kabushiki kaisha organized under the laws of Japan (now known as Dai-ichi Life Holdings, Inc., “Dai-ichi Life”), when DL Investment (Delaware), Inc. a wholly owned subsidiary of Dai-ichi Life, merged with and into PLC (the “Merger”). Prior to February 1, 2015, PLC’s stock was publicly traded on the New York Stock Exchange. Subsequent to the Merger, PLC remained an SEC registrant within the United States until January 23, 2020, when it suspended its reporting obligations with the SEC under the Securities Exchange Act of 1934. The Company has continued to be an SEC registrant for financial reporting purposes in the United States. The Company markets individual life insurance, credit life and disability insurance, guaranteed investment contracts, guaranteed funding agreements, fixed and variable annuities, and extended service contracts throughout the United States. The Company also maintains a separate segment devoted to the acquisition of insurance policies from other companies. PLC is a holding company with subsidiaries that provide financial services through the production, distribution, and administration of insurance and investment products. These consolidated condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for the interim periods presented herein. In the opinion of management, the accompanying consolidated condensed financial statements reflect all adjustments (consisting only of normal recurring items) necessary for a fair presentation of the results for the interim periods presented. Operating results for the three months ended March 31, 2020, are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2020. The year end consolidated condensed financial data included herein was derived from audited financial statements but this report does not include all disclosures required by GAAP. For further information, refer to the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019. The operating results of companies in the insurance industry have historically been subject to significant fluctuations due to changing competition, economic conditions, interest rates, investment performance, insurance ratings, claims, persistency, and other factors.
Reclassifications	In the first quarter, the uncontained outbreak of the novel coronavirus, which causes the disease termed COVID-19, created significant economic and social disruption and impacted various operational and financial aspects of the Company's business. While not all of the impacts of COVID-19 are identifiable or quantifiable, as of March 31, 2020, the deterioration in actual and forecasted macroeconomic variables have adversely impacted the market values of certain of the Company's investments and its allowance for credit losses on commercial mortgage loans. Also, the Company has recorded an increase associated with guaranteed benefits on certain of its variable annuity contracts, while realizing gains from derivatives held to hedge these guaranteed benefits.
Entities Included	Entities Included The consolidated condensed financial statements in this report include the accounts of Protective Life Insurance Company and affiliate companies in which the Company holds a majority voting or economic interest. Intercompany balances and transactions have been eliminated.
Accounting Pronouncements Recently Adopted and Not Yet Adopted	Accounting Pronouncements Recently Adopted Accounting Standards Update(“ASU”) No. 2016-13 - Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. The amendments in this Update introduce a new current expected credit loss (“CECL”) model for certain financial assets, including mortgage loans and reinsurance receivables. For assets within the scope of the new model, an entity will recognize as an allowance against earnings its estimate of the contractual cash flows not expected to be collected on day one of the asset’s acquisition. The allowance may be reversed through earnings if a security recovers in value. This differs from the current impairment model, which requires recognition of credit losses when they have been incurred and recognizes a security’s subsequent recovery in value in other comprehensive income. The Update also makes targeted changes to the current impairment model for available-for-sale debt securities, which comprise the majority of the Company’s invested assets. Similar to the CECL model, credit loss impairments will be recorded in an allowance against earnings that may be reversed for subsequent recoveries in value. The amendments in this Update, along with related amendments in ASU No. 2018-19, ASU No. 2019-04, and ASU No. 2019-11 - Codification Improvements to Topic 326, Financial Instruments-Credit Losses, are effective for annual and interim periods beginning after December 15, 2019 on a modified retrospective basis. A vendor-provided credit loss model will be used to measure the allowance for the majority of the Company’s commercial mortgage loans and unfunded mortgage loan commitments, and the Company will use an internally-developed model to measure the allowance for amounts recoverable from reinsurers. The Company applied the revisions in the Update through a cumulative effect adjustment to retained earnings as of January 1, 2020. The cumulative effect adjustment resulted in a decrease in retained earnings of $138.1 million, net of the impact to deferred taxes, deferred acquisition costs (“DAC”), value of business acquired (“VOBA”) and other items. The Company continues to apply the previous guidance to 2019 and prior periods. Accounting Pronouncements Not Yet Adopted ASU No. 2018-12 - Financial Services - Insurance (Topic 944): Targeted Improvements to Accounting for Long-Duration Contracts. The amendments in this Update are designed to make improvements to the existing recognition, measurement, presentation, and disclosure requirements for certain long-duration contracts issued by an insurance company. The new amendments require insurance entities to provide a more current measure of the liability for future policy benefits for traditional and limited-payment contracts by regularly refining the liability for actual past experience and updated future assumptions. This differs from current requirements where assumptions are locked-in at contract issuance for these contract types. In addition, the updated liability will be discounted using an upper-medium grade (low-credit-risk) fixed income instrument yield that reflects the characteristics of the liability which differs from currently used rates based on the invested assets supporting the liability. In addition, the amendments introduce new requirements to assess market-based insurance contract options and guarantees for Market Risk Benefits and measure them at fair value. This Update also requires insurance entities to amortize deferred acquisition costs on a constant-level basis over the expected life of the contract. Finally, this Update requires new disclosures including liability rollforwards and information about significant inputs, judgments, assumptions, and methods used in the measurement. The amendments in this Update were originally effective for periods beginning after December 15, 2020. However, in November 2019, the Financial Accounting Standards Board (the “FASB”) issued ASU No. 2019-09 – Financial Services – Insurance (Topic 944): Effective Date which extended the implementation deadline by one year to periods beginning after December 15, 2021. The Company is currently reviewing its policies, processes, and applicable systems to determine the impact this standard will have on its operations and financial results. ASU No. 2019-12 – Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The amendments in this Update remove certain exceptions to the general principles in Topic 740 related to intraperiod tax allocations, interim tax calculations, and outside basis differences. The amendments also clarify and amend guidance in certain other areas of Topic 740 in order to eliminate diversity in practice. The amendments in this Update are effective for public business entities in fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company is reviewing its accounting policies and processes to ensure compliance with the revised guidance, upon adoption.