Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation: The accompanying condensed consolidated financial statements of Torchmark Corporation (Torchmark or alternatively, the Company) have been prepared in accordance with the instructions to Form 10-Q. Therefore, they do not include all of the annual disclosures required by accounting principles generally accepted in the United States of America (GAAP). However, in the opinion of management, these statements include all adjustments, consisting of normal recurring adjustments, which are necessary for a fair presentation of the condensed consolidated financial position at September 30, 2017, and the condensed consolidated results of operations, comprehensive income, and cash flows for the periods ended September 30, 2017 and 2016. The interim period condensed consolidated financial statements should be read in conjunction with the Consolidated Financial Statements that are included in the Form 10-K filed with the Securities Exchange Commission (SEC) on February 27, 2017.
Accounting Pronouncements Not Yet Adopted	Accounting Pronouncements Not Yet Adopted ASU 2016-01: In January 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which primarily revises the classification and measurement of certain equity investments such that they will be measured at fair value through net income. Additionally, it eliminates the cost method for partnerships and joint ventures and requires these types of investments to be accounted for under the fair value through net income method or equity method. Lastly, the guidance will require certain disclosures associated with fair value of financial instruments. This standard will become effective for the Company beginning January 1, 2018. The adoption will not have a significant impact on the financial statements as we have limited ownership in equity investments and partnerships, representing less than 1% of total invested assets. ASU 2016-02: In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which requires all lessees to report a right-of-use asset and a lease liability for leases with a term life greater than 12 months. Operating and financing leases will be recognized on the balance sheet going forward. Additional qualitative and quantitative disclosures will be required. This standard will become effective for the Company beginning January 1, 2019 and will require recognizing and measuring leases at the beginning of the earliest period presented using a modified retrospective approach. Early adoption is permitted. The Company does not expect the adoption to have a significant impact on the financial statements. Refer to the 2016 Form 10-K Note 15—Commitments and Contingencies for consideration of the noncancellable operating lease commitments. The Company does not have any lessor commitments. ASU 2016-13: In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments as well as to change the loss impairment methodology for available-for-sale debt securities. This standard will become effective on January 1, 2020. The applicable section of the standard related to debt securities requires a prospective transition. The Company does not expect the adoption to have a significant impact on the financial statements as we have limited credit losses with respect to our available-for-sale portfolio. ASU 2016-15: In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments to provide uniformity in the classification of cash receipts and payments recorded in the statement of cash flows including debt prepayment or debt extinguishment costs, settlement of zero-coupon bonds, and proceeds from the settlement of insurance claims. This standard will become effective on January 1, 2018 and will not have a significant impact on the financial statements. ASU 2016-16: In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfer of Assets Other Than Inventory. This guidance was issued to improve the accounting for income tax consequences of intra-entity transfers of assets other than inventory by allowing the immediate recognition of the current and deferred income tax effects. Current guidance prohibits the recognition of current and deferred income taxes for an intra-entity transfer until the asset has been sold to an outside party. This new guidance should be applied on a modified retrospective approach and will become effective on January 1, 2018. This adoption will not have a significant impact on the financial statements. ASU 2017-04: In January 2017, the FASB issued ASU No. 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. This guidance was issued to simplify the subsequent measurement of goodwill through the elimination of Step 2 from the goodwill impairment test which required a hypothetical purchase price allocation. It will become effective on January 1, 2020 and should be applied on a prospective basis. This adoption will not have a significant impact on the financial statements. ASU 2017-07: In March 2017, the FASB issued ASU No. 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. This guidance was issued to simplify the reporting of pension costs by disaggregating the service-cost component from the other components of net benefit costs and reporting it separately on the income statement. The service-cost component is the only component of net benefit cost that will be eligible for capitalization. The guidance will become effective on January 1, 2018 with a retrospective transition method for separation of net benefit costs and a prospective transition method for the capitalization of service costs. The Company does not expect the adoption to have a significant impact on the financial statements as the change in pension capitalization should be less than 1% of Total Benefits and Expenses on the Consolidated Statement of Operations for the year. ASU 2017-08: In March 2017, the FASB issued ASU No. 2017-08, Receivables—Nonrefundable Fees and Other Costs (Topic 310-20): Premium Amortization on Purchased Callable Debt Securities. This guidance was issued to shorten the amortization period for certain callable debt securities held at a premium. The guidance requires the premium to be amortized to the earliest call date. It will become effective on January 1, 2019 with early adoption permitted, including during interim periods. The adoption is to be applied on a modified retrospective basis through an adjustment to retained earnings. This adoption will not have a significant impact on the financial statements. ASU 2017-09: In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting. This guidance was issued to provide clarity and guidance regarding changes to the terms or conditions of a share-based payment award that requires an entity to apply modification accounting. It will become effective on January 1, 2018 with early adoption permitted, including adoption in any interim periods. The Company does not expect the adoption to have a significant impact on the financial statements as modifications to stock compensation are infrequent.

Accounting Pronouncements Not Yet Adopted

ASU 2016-01: In January 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which primarily revises the classification and measurement of certain equity investments such that they will be measured at fair value through net income. Additionally, it eliminates the cost method for partnerships and joint ventures and requires these types of investments to be accounted for under the fair value through net income method or equity method. Lastly, the guidance will require certain disclosures associated with fair value of financial instruments. This standard will become effective for the Company beginning January 1, 2018. The adoption will not have a significant impact on the financial statements as we have limited ownership in equity investments and partnerships, representing less than 1% of total invested assets.

ASU 2016-02: In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which requires all lessees to report a right-of-use asset and a lease liability for leases with a term life greater than 12 months. Operating and financing leases will be recognized on the balance sheet going forward. Additional qualitative and quantitative disclosures will be required. This standard will become effective for the Company beginning January 1, 2019 and will require recognizing and measuring leases at the beginning of the earliest period presented using a modified retrospective approach. Early adoption is permitted. The Company does not expect the adoption to have a significant impact on the financial statements. Refer to the 2016 Form 10-K Note 15—Commitments and Contingencies for consideration of the noncancellable operating lease commitments. The Company does not have any lessor commitments.

ASU 2016-13: In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments as well as to change the loss impairment methodology for available-for-sale debt securities. This standard will become effective on January 1, 2020. The applicable section of the standard related to debt securities requires a prospective transition. The Company does not expect the adoption to have a significant impact on the financial statements as we have limited credit losses with respect to our available-for-sale portfolio.

ASU 2016-15: In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments to provide uniformity in the classification of cash receipts and payments recorded in the statement of cash flows including debt prepayment or debt extinguishment costs, settlement of zero-coupon bonds, and proceeds from the settlement of insurance claims. This standard will become effective on January 1, 2018 and will not have a significant impact on the financial statements.

ASU 2016-16: In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfer of Assets Other Than Inventory. This guidance was issued to improve the accounting for income tax consequences of intra-entity transfers of assets other than inventory by allowing the immediate recognition of the current and deferred income tax effects. Current guidance prohibits the recognition of current and deferred income taxes for an intra-entity transfer until the asset has been sold to an outside party. This new guidance should be applied on a modified retrospective approach and will become effective on January 1, 2018. This adoption will not have a significant impact on the financial statements.

ASU 2017-04: In January 2017, the FASB issued ASU No. 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. This guidance was issued to simplify the subsequent measurement of goodwill through the elimination of Step 2 from the goodwill impairment test which required a hypothetical purchase price allocation. It will become effective on January 1, 2020 and should be applied on a prospective basis. This adoption will not have a significant impact on the financial statements.

ASU 2017-07: In March 2017, the FASB issued ASU No. 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. This guidance was issued to simplify the reporting of pension costs by disaggregating the service-cost component from the other components of net benefit costs and reporting it separately on the income statement. The service-cost component is the only component of net benefit cost that will be eligible for capitalization. The guidance will become effective on January 1, 2018 with a retrospective transition method for separation of net benefit costs and a prospective transition method for the capitalization of service costs. The Company does not expect the adoption to have a significant impact on the financial statements as the change in pension capitalization should be less than 1% of Total Benefits and Expenses on the Consolidated Statement of Operations for the year.

ASU 2017-08: In March 2017, the FASB issued ASU No. 2017-08, Receivables—Nonrefundable Fees and Other Costs (Topic 310-20): Premium Amortization on Purchased Callable Debt Securities. This guidance was issued to shorten the amortization period for certain callable debt securities held at a premium. The guidance requires the premium to be amortized to the earliest call date. It will become effective on January 1, 2019 with early adoption permitted, including during interim periods. The adoption is to be applied on a modified retrospective basis through an adjustment to retained earnings. This adoption will not have a significant impact on the financial statements.

ASU 2017-09: In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting. This guidance was issued to provide clarity and guidance regarding changes to the terms or conditions of a share-based payment award that requires an entity to apply modification accounting. It will become effective on January 1, 2018 with early adoption permitted, including adoption in any interim periods. The Company does not expect the adoption to have a significant impact on the financial statements as modifications to stock compensation are infrequent.