Globe Life (GL) 10-Q 8 Aug 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 31, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	TORCHMARK CORP
Entity Central Index Key	320,335
Trading Symbol	TMK
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		112,693,381

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Investments:
Fixed maturities—available for sale, at fair value (amortized cost: 2018—$15,350,152; 2017—$14,995,101)	$ 16,284,691	$ 16,969,325
Policy loans	537,808	529,529
Other long-term investments (includes: 2018—$108,452; 2017—$0, under the fair value option)	181,676	108,559
Short-term investments	68,544	127,071
Total investments	17,072,719	17,734,484
Cash	82,230	118,563
Accrued investment income	237,985	233,453
Other receivables	407,676	391,775
Deferred acquisition costs	4,045,890	3,958,063
Goodwill	441,591	441,591
Other assets	522,042	528,536
Assets related to discontinued operations	68,568	68,520
Total assets	22,878,701	23,474,985
Liabilities:
Future policy benefits	13,702,887	13,439,472
Unearned and advance premiums	66,872	61,430
Policy claims and other benefits payable	329,469	333,294
Other policyholders' funds	96,575	97,635
Total policy liabilities	14,195,803	13,931,831
Current and deferred income taxes payable	1,098,411	1,312,002
Other liabilities	474,264	489,609
Short-term debt	671,666	328,067
Long-term debt (estimated fair value: 2018—$849,903; 2017—$1,228,392)	817,474	1,132,201
Liabilities related to discontinued operations	49,474	49,854
Total liabilities	17,307,092	17,243,564
Commitments and Contingencies (Note 6)
Shareholders’ equity:
Preferred stock, par value $1 per share—Authorized 5,000,000 shares; outstanding: -0- in 2018 and 2017	0	0
Common stock, par value $1 per share—Authorized 320,000,000 shares; outstanding: (2018—124,218,183 issued, less 11,294,710 held in treasury and 2017—124,218,183 issued, less 9,625,104 held in treasury)	124,218	124,218
Additional paid-in capital	517,077	508,476
Accumulated other comprehensive income	603,499	1,424,274
Retained earnings	5,115,071	4,806,208
Treasury stock, at cost	(788,256)	(631,755)
Total shareholders’ equity	5,571,609	6,231,421
Total liabilities and shareholders’ equity	$ 22,878,701	$ 23,474,985

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fixed maturities, available for sale, amortized cost	$ 15,350,152	$ 14,995,101
Long-term debt, fair value	$ 849,903	$ 1,228,392
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	320,000,000	320,000,000
Common stock, shares issued (in shares)	124,218,183	124,218,183
Common stock, shares held in treasury (in shares)	11,294,710	9,625,104
Fair Value Option [Member]
Fair value option	$ 108,452
Partnership Interest [Member] | Fair Value Option [Member]
Fair value option	$ 108,452	$ 0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue:
Total premium	$ 853,979	$ 816,614	$ 1,704,085	$ 1,637,245
Net investment income	218,568	212,776	436,652	421,058
Realized investment gains (losses)	11,813	(705)	13,764	(6,453)
Other income	416	393	711	809
Total revenue	1,084,776	1,029,078	2,155,212	2,052,659
Benefits and expenses:
Life policyholder benefits	399,334	390,859	799,915	781,938
Health policyholder benefits	160,461	156,579	321,080	314,330
Other policyholder benefits	8,582	8,977	17,271	17,923
Total policyholder benefits	568,377	556,415	1,138,266	1,114,191
Amortization of deferred acquisition costs	129,077	122,121	258,697	248,029
Commissions, premium taxes, and non-deferred acquisition costs	69,427	65,032	139,066	130,148
Other operating expense	68,620	62,428	135,444	124,769
Interest expense	22,411	21,156	44,033	41,855
Total benefits and expenses	857,912	827,152	1,715,506	1,658,992
Income before income taxes	226,864	201,926	439,706	393,667
Income taxes	(42,471)	(61,563)	(81,602)	(116,126)
Income from continuing operations	184,393	140,363	358,104	277,541
Income (loss) from discontinued operations, net of tax	32	(90)	(79)	(3,727)
Net income	$ 184,425	$ 140,273	$ 358,025	$ 273,814
Basic net income (loss) per common share:
Continuing operations (in dollars per share)	$ 1.63	$ 1.20	$ 3.15	$ 2.37
Discontinued operations (in dollars per share)	0	0	0	(0.03)
Total basic net income per common share (in dollars per share)	1.63	1.20	3.15	2.34
Diluted net income (loss) per common share:
Continuing operations (in dollars per share)	1.59	1.18	3.08	2.32
Discontinued operations (in dollars per share)	0	0	0	(0.03)
Total diluted net income per common share (in dollars per share)	1.59	1.18	3.08	2.29
Dividends declared per common share (in dollars per share)	$ 0.16	$ 0.15	$ 0.32	$ 0.3
Life premium [Member]
Revenue:
Total premium	$ 602,534	$ 573,836	$ 1,200,837	$ 1,149,673
Health premium [Member]
Revenue:
Total premium	251,440	242,775	503,238	487,566
Other premium [Member]
Revenue:
Total premium	$ 5	$ 3	$ 10	$ 6

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income	$ 184,425	$ 140,273	$ 358,025	$ 273,814
Investments:
Total unrealized investment gains (losses)	(425,805)	396,929	(1,041,487)	611,995
Less applicable tax (expense) benefit	89,423	(138,931)	218,712	(214,254)
Unrealized investment gains (losses), net of tax	(336,382)	257,998	(822,775)	397,741
Deferred acquisition costs:
Unrealized gains (losses) attributable to deferred acquisition costs	2,041	(727)	2,491	(1,497)
Less applicable tax (expense) benefit	(429)	254	(523)	524
Unrealized gains (losses) attributable to deferred acquisition costs, net of tax	1,612	(473)	1,968	(973)
Foreign exchange translation:
Foreign exchange translation adjustments, other than securities	(6,217)	3,302	(7,516)	7,516
Less applicable tax (expense) benefit	1,303	(1,153)	1,579	(1,581)
Foreign exchange translation adjustments, other than securities, net of tax	(4,914)	2,149	(5,937)	5,935
Pension:
Amortization of pension costs	3,778	3,109	7,556	6,218
Experience gain (loss)	0	0	0	371
Pension adjustments	3,778	3,109	7,556	6,589
Less applicable tax (expense) benefit	(794)	(1,088)	(1,587)	(2,306)
Pension adjustments, net of tax	2,984	2,021	5,969	4,283
Other comprehensive income (loss)	(336,700)	261,695	(820,775)	406,986
Comprehensive income (loss)	(152,275)	401,968	(462,750)	680,800
Securities [Member]
Investments:
Unrealized holding gains (losses) arising during period	(417,616)	394,004	(1,029,164)	609,531
Reclassification adjustment for (gains) losses on securities included in net income	(9,431)	681	(10,817)	(354)
Reclassification adjustment for amortization of (discount) and premium	870	(61)	1,560	(498)
Foreign exchange adjustment on securities recorded at fair value	(679)	230	(1,264)	245
Unrealized gains (losses) on securities	(426,856)	394,854	(1,039,685)	608,924
Other Investments [Member]
Investments:
Unrealized gains (losses) on other investments	$ 1,051	$ 2,075	$ (1,802)	$ 3,071

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands		Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Treasury Stock [Member]
Stockholders' equity, beginning balance at Dec. 31, 2016		$ 4,566,861	$ 0	$ 127,218	$ 490,421	$ 577,574	$ 3,890,798	$ (519,150)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)		680,800				406,986	273,814
Common dividends declared ($0.30 in 2017 and $0.32 in 2018)		(35,005)					(35,005)
Acquisition of treasury stock		(203,756)						(203,756)
Stock-based compensation		16,546			9,702		(606)	7,450
Exercise of stock options		27,970					(16,244)	44,214
Stockholders' equity, ending balance at Jun. 30, 2017		5,053,416	0	127,218	500,123	984,560	4,112,757	(671,242)
Stockholders' equity, beginning balance at Mar. 31, 2017						722,865
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)		401,968
Stockholders' equity, ending balance at Jun. 30, 2017		5,053,416	0	127,218	500,123	984,560	4,112,757	(671,242)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU 2016-01	[1]	4,896					4,896
Stockholders' equity, beginning balance at Dec. 31, 2017		6,231,421	0	124,218	508,476	1,424,274	4,806,208	(631,755)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)		(462,750)				(820,775)	358,025
Common dividends declared ($0.30 in 2017 and $0.32 in 2018)		(36,278)					(36,278)
Acquisition of treasury stock		(206,589)						(206,589)
Stock-based compensation		19,557			8,601		(1,803)	12,759
Exercise of stock options		21,352					(15,977)	37,329
Stockholders' equity, ending balance at Jun. 30, 2018		5,571,609	0	124,218	517,077	603,499	5,115,071	(788,256)
Stockholders' equity, beginning balance at Mar. 31, 2018						940,199
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)		(152,275)
Stockholders' equity, ending balance at Jun. 30, 2018		$ 5,571,609	$ 0	$ 124,218	$ 517,077	$ 603,499	$ 5,115,071	$ (788,256)
[1]	See further discussion in Note 2—New Accounting Standards and Note 4—Investments.

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share (in dollars per share)	$ 0.16	$ 0.15	$ 0.32	$ 0.3

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Statement of Cash Flows [Abstract]
Cash provided from operating activities	$ 616,520	$ 739,056
Investments sold or matured:
Fixed maturities available for sale—matured, called, and repaid	179,793	216,170
Other long-term investments	23	3,046
Total long-term investments sold or matured	179,816	219,216
Acquisition of investments:
Fixed maturities—available for sale	(540,442)	(676,648)
Other long-term investments	(64,444)	(1,775)
Total investments acquired	(604,886)	(678,423)
Net (increase) decrease in policy loans	(8,279)	(8,089)
Net (increase) decrease in short-term investments	58,527	(22,347)
Additions to property and equipment	(18,735)	(8,080)
Sale of other assets	17	18
Investment in low-income housing interests	(15,701)	(8,875)
Cash provided from (used for) investing activities	(409,241)	(506,580)
Cash provided from (used for) financing activities:
Issuance of common stock	21,352	27,970
Cash dividends paid to shareholders	(35,406)	(34,093)
Repayment of debt	(21,875)	(625)
Net borrowing (repayment) of commercial paper	50,213	40,546
Acquisition of treasury stock	(206,589)	(203,756)
Net receipts (payments) from deposit-type product	(58,662)	(44,294)
Cash provided from (used for) financing activities	(250,967)	(214,252)
Effect of foreign exchange rate changes on cash	7,355	3,265
Net increase (decrease) in cash	(36,333)	21,489
Cash at beginning of year	118,563	76,163
Cash at end of period	$ 82,230	$ 97,652

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies 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 June 30, 2018 , and the condensed consolidated results of operations, comprehensive income, and cash flows for the periods ended June 30, 2018 and 2017 . 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 26, 2018.

New Accounting Standards

New Accounting Standards	6 Months Ended
	Jun. 30, 2018
Accounting Changes and Error Corrections [Abstract]
New Accounting Standards	New Accounting Standards Accounting Pronouncements Adopted in the Current Year: 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, the guidance 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 or equity method. This standard became effective for the Company on January 1, 2018. On January 1, 2018, the Company adopted this standard on a modified retrospective basis for two types of investments: equity securities and limited partnerships. The adoption resulted in a $4.9 million after tax positive adjustment to the opening balance of retained earnings. Subsequent to the adoption, the Company elected to measure its investment in certain limited partnerships at fair value in accordance with the fair value option for financial instruments with changes recognized in "Realized Investment Gains (Losses)" in the Condensed Consolidated Statements of Operations . As of June 30, 2018 , the fair value balance of the limited partnerships were $108 million . See Note 4—Investments for further discussion. 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 became effective on January 1, 2018 and did not have a significant impact to the classification on the Condensed Statement of Cash Flows . 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 guidance is applied on a modified retrospective approach and became effective on January 1, 2018. This adoption did 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 became 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 will record approximately $3.5 million in additional expense to the 2018 Condensed Consolidated Statements of Operations due to the elimination of the ability to capitalize a portion of the benefit costs. For the six months ended June 30, 2018 , the Company recorded $1.6 million in additional expense. 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 became effective on January 1, 2018. The adoption had no significant impact on the financial statements as modifications to stock compensation are infrequent. ASU 2018-02 : In February 2018, the FASB issued ASU No. 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (AOCI) . This guidance was issued to allow the reclassification of taxes from AOCI to retained earnings as a result of the reduction in corporate income tax rates due to the Tax Cuts and Jobs Act of 2017 (Tax Legislation). Current accounting requires the effect of changes in tax rates used to measure deferred tax assets and liabilities to be reported in net income as of the date of enactment even though deferred taxes were previously recognized in AOCI (stranded taxes). This guidance, however, allows a company to elect to reclassify the stranded taxes in AOCI to retained earnings and is effective for years beginning after December 15, 2018, with early adoption permitted. The Company elected to early adopt this guidance resulting in a reclassification of $252 million from AOCI to retained earnings for the period ended December 31, 2017. Accounting Pronouncements Not Yet Adopted ASU 2016-02/ASU 2018-11: In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), with clarification guidance issued in July 2018. The guidance requires lessees to record a right-of-use asset and corresponding lease liability on the balance sheet for all operating leases that do not qualify for the practical expedients allowed for in this standard. Additional qualitative and quantitative disclosures will be required. This standard will become effective for the Company beginning January 1, 2019. The Company plans to adopt the transition method allowed for under ASU 2018-11 and will not restate comparative periods upon adoption. Early adoption is permitted. The Company does not expect the adoption to have a significant impact on the financial statements. Refer to Note 15—Commitments and Contingencies of the 2017 10-K for consideration of the noncancelable operating lease commitments. The Company is not a lessor. 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 by use of an allowance rather than a direct write-down. 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 current available-for-sale portfolio. 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 an impact to the financial statements. 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.

Supplemental Information about

Supplemental Information about Changes to Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Supplemental Information about Changes to Accumulated Other Comprehensive Income	Supplemental Information about Changes to Accumulated Other Comprehensive Income An analysis of the change in balance by component of Accumulated Other Comprehensive Income is as follows for the three and six month periods ended June 30, 2018 and 2017 . Components of Accumulated Other Comprehensive Income Three Months Ended June 30, 2017 Available Deferred Foreign Pension Total Balance at April 1, 2017 $ 832,057 $ (7,182 ) $ 8,753 $ (110,763 ) $ 722,865 Other comprehensive income (loss) before reclassifications, net of tax 257,595 (473 ) 2,149 — 259,271 Reclassifications, net of tax 403 — — 2,021 2,424 Other comprehensive income (loss) 257,998 (473 ) 2,149 2,021 261,695 Balance at June 30, 2017 $ 1,090,055 $ (7,655 ) $ 10,902 $ (108,742 ) $ 984,560 Three Months Ended June 30, 2018 Available Deferred Foreign Pension Total Balance at April 1, 2018 $ 1,082,896 $ (8,191 ) $ 15,279 $ (149,785 ) $ 940,199 Other comprehensive income (loss) before reclassifications, net of tax (329,619 ) 1,612 (4,914 ) — (332,921 ) Reclassifications, net of tax (6,763 ) — — 2,984 (3,779 ) Other comprehensive income (loss) (336,382 ) 1,612 (4,914 ) 2,984 (336,700 ) Balance at June 30, 2018 $ 746,514 $ (6,579 ) $ 10,365 $ (146,801 ) $ 603,499 Six Months Ended June 30, 2017 Available Deferred Foreign Pension Total Balance at January 1, 2017 $ 692,314 $ (6,682 ) $ 4,967 $ (113,025 ) $ 577,574 Other comprehensive income (loss) before reclassifications, net of tax 398,295 (973 ) 5,935 241 403,498 Reclassifications, net of tax (554 ) — — 4,042 3,488 Other comprehensive income (loss) 397,741 (973 ) 5,935 4,283 406,986 Balance at June 30, 2017 $ 1,090,055 $ (7,655 ) $ 10,902 $ (108,742 ) $ 984,560 Six Months Ended June 30, 2018 Available Deferred Foreign Pension Total Balance at January 1, 2018 $ 1,569,289 $ (8,547 ) $ 16,302 $ (152,770 ) $ 1,424,274 Other comprehensive income (loss) before reclassifications, net of tax (815,462 ) 1,968 (5,937 ) — (819,431 ) Reclassifications, net of tax (7,313 ) — — 5,969 (1,344 ) Other comprehensive income (loss) (822,775 ) 1,968 (5,937 ) 5,969 (820,775 ) Balance at June 30, 2018 $ 746,514 $ (6,579 ) $ 10,365 $ (146,801 ) $ 603,499 Reclassifications out of Accumulated Other Comprehensive Income are presented below for the three and six month periods ended June 30, 2018 and 2017 . Reclassification Adjustments Three Months Ended Six Months Ended Affected line items in the Statement of Operations 2018 2017 2018 2017 Unrealized investment gains (losses) on available for sale assets: Realized (gains) losses $ (9,431 ) $ 681 $ (10,817 ) $ (354 ) Realized investment gains (losses) Amortization of (discount) premium 870 (61 ) 1,560 (498 ) Net investment income Total before tax (8,561 ) 620 (9,257 ) (852 ) Tax 1,798 (217 ) 1,944 298 Income taxes Total after tax (6,763 ) 403 (7,313 ) (554 ) Pension adjustments: Amortization of prior service cost 119 119 238 238 Other operating expense Amortization of actuarial gain (loss) 3,659 2,990 7,318 5,980 Other operating expense Total before tax 3,778 3,109 7,556 6,218 Tax (794 ) (1,088 ) (1,587 ) (2,176 ) Income taxes Total after tax 2,984 2,021 5,969 4,042 Total reclassifications (after tax) $ (3,779 ) $ 2,424 $ (1,344 ) $ 3,488

Investments

Investments	6 Months Ended
	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Portfolio Composition : A summary of fixed maturities available for sale by cost or amortized cost and estimated fair value at June 30, 2018 and December 31, 2017 is as follows: June 30, 2018 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (1) % of Total Fixed Maturities (2) Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 390,021 $ 2,266 $ (4,383 ) $ 387,904 2 States, municipalities, and political subdivisions 1,232,142 103,365 (281 ) 1,335,226 9 Foreign governments 19,609 1,705 — 21,314 — Corporates, by sector: Financial 3,372,221 269,494 (51,445 ) 3,590,270 22 Utilities 1,947,899 255,504 (12,164 ) 2,191,239 14 Energy 1,619,674 133,584 (40,101 ) 1,713,157 11 Other corporate sectors 6,183,619 362,020 (146,563 ) 6,399,076 39 Total corporates 13,123,413 1,020,602 (250,273 ) 13,893,742 86 Collateralized debt obligations 58,582 23,437 (5,823 ) 76,196 — Other asset-backed securities 150,843 2,386 (429 ) 152,800 1 Redeemable preferred stocks, by sector: Financial 347,014 45,481 (4,518 ) 387,977 2 Utilities 28,528 1,360 (356 ) 29,532 — Total redeemable preferred stocks 375,542 46,841 (4,874 ) 417,509 2 Total fixed maturities $ 15,350,152 $ 1,200,602 $ (266,063 ) $ 16,284,691 100 (1) Amounts reported on the balance sheet. (2) At fair value. December 31, 2017 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (1) % of Total Fixed Maturities (2) Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 390,646 $ 18,173 $ (1,373 ) $ 407,446 2 States, municipalities, and political subdivisions 1,091,960 127,890 (135 ) 1,219,715 7 Foreign governments 20,236 1,782 — 22,018 — Corporates, by sector: Financial 3,282,526 475,961 (23,392 ) 3,735,095 22 Utilities 1,955,737 369,406 (1,298 ) 2,323,845 14 Energy 1,619,349 226,140 (25,392 ) 1,820,097 11 Other corporate sectors 6,065,803 747,612 (20,616 ) 6,792,799 40 Total corporates 12,923,415 1,819,119 (70,698 ) 14,671,836 87 Collateralized debt obligations 59,150 20,084 (7,653 ) 71,581 — Other asset-backed securities 144,520 4,835 — 149,355 1 Redeemable preferred stocks, by sector: Financial 336,621 62,892 (2,727 ) 396,786 3 Utilities 28,553 2,132 (97 ) 30,588 — Total redeemable preferred stocks 365,174 65,024 (2,824 ) 427,374 3 Total fixed maturities $ 14,995,101 $ 2,056,907 $ (82,683 ) $ 16,969,325 100 (1) Amounts reported on the balance sheet. (2) At fair value. A schedule of fixed maturities available for sale by contractual maturity date at June 30, 2018 is shown below on an amortized cost basis and on a fair value basis. Actual disposition dates could differ from contractual maturities due to call or prepayment provisions. June 30, 2018 Amortized Fair Value Fixed maturities available for sale: Due in one year or less $ 80,564 $ 81,901 Due after one year through five years 732,395 757,040 Due after five years through ten years 1,611,476 1,745,491 Due after ten years through twenty years 5,051,297 5,607,509 Due after twenty years 7,664,183 7,862,890 Mortgage-backed and asset-backed securities 210,237 229,860 $ 15,350,152 $ 16,284,691 There were no sales of fixed maturities available for sale as of June 30, 2018 or 2017 . Fair Value Measurements : The following tables represents the fair value of fixed maturities available for sale measured on a recurring basis at June 30, 2018 and December 31, 2017 . Fair Value Measurements at June 30, 2018 using: Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ — $ 387,904 $ — $ 387,904 States, municipalities, and political subdivisions — 1,335,226 — 1,335,226 Foreign governments — 21,314 — 21,314 Corporates, by sector: Financial — 3,529,651 60,619 3,590,270 Utilities — 2,044,141 147,098 2,191,239 Energy — 1,673,305 39,852 1,713,157 Other corporate sectors — 6,069,835 329,241 6,399,076 Total corporates — 13,316,932 576,810 13,893,742 Collateralized debt obligations — — 76,196 76,196 Other asset-backed securities — 139,647 13,153 152,800 Redeemable preferred stocks, by sector: Financial — 387,977 — 387,977 Utilities — 29,532 — 29,532 Total redeemable preferred stocks — 417,509 — 417,509 Total fixed maturities $ — $ 15,618,532 $ 666,159 $ 16,284,691 Percent of total — % 95.9 % 4.1 % 100.0 % Fair Value Measurements at December 31, 2017 using: Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ — $ 407,446 $ — $ 407,446 States, municipalities, and political subdivisions 44 1,219,671 — 1,219,715 Foreign governments — 22,018 — 22,018 Corporates, by sector: Financial — 3,673,089 62,006 3,735,095 Utilities — 2,168,115 155,730 2,323,845 Energy — 1,779,281 40,816 1,820,097 Other corporate sectors — 6,468,541 324,258 6,792,799 Total corporates — 14,089,026 582,810 14,671,836 Collateralized debt obligations — — 71,581 71,581 Other asset-backed securities — 135,306 14,049 149,355 Redeemable preferred stocks, by sector: Financial — 396,786 — 396,786 Utilities — 30,588 — 30,588 Total redeemable preferred stocks — 427,374 — 427,374 Total fixed maturities $ 44 $ 16,300,841 $ 668,440 $ 16,969,325 Percentage of total — % 96.1 % 3.9 % 100.0 % The following tables represent an analysis of changes in fair value measurements using significant unobservable inputs (Level 3) for the six months ended June 30, 2018 and 2017 . Analysis of Changes in Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six Months Ended June 30, 2018 Asset- Collateralized Corporates (1) Total Balance at January 1, 2018 $ 14,049 $ 71,581 $ 582,810 $ 668,440 Total gains or losses: Included in realized gains/losses — — — — Included in other comprehensive income (697 ) 5,183 (19,611 ) (15,125 ) Acquisitions — — 20,300 20,300 Sales — — — — Amortization — 2,389 8 2,397 Other (2) (199 ) (2,957 ) (6,697 ) (9,853 ) Transfers in and/or out of Level 3 (3) — — — — Balance at June 30, 2018 $ 13,153 $ 76,196 $ 576,810 $ 666,159 Percent of total fixed maturities 0.1 % 0.5 % 3.5 % 4.1 % (1) Includes redeemable preferred stocks. (2) Includes capitalized interest, foreign exchange adjustments, and principal repayments. (3) Considered to be transferred at the end of the period. Transfers into Level 3 occur when observable inputs are no longer available. Transfers out of Level 3 occur when observable inputs become available. Six Months Ended June 30, 2017 Asset- Collateralized Corporates (1) Total Balance at January 1, 2017 $ — $ 63,503 $ 559,600 $ 623,103 Total gains or losses: Included in realized gains/losses — — — — Included in other comprehensive income 261 3,597 11,637 15,495 Acquisitions 14,000 — 21,666 35,666 Sales — — — — Amortization — 2,481 8 2,489 Other (2) (108 ) (3,336 ) (6,625 ) (10,069 ) Transfers in and/or out of Level 3 (3) — — — — Balance at June 30, 2017 $ 14,153 $ 66,245 $ 586,286 $ 666,684 Percent of total fixed maturities 0.1 % 0.4 % 3.6 % 4.1 % (1) Includes redeemable preferred stocks. (2) Includes capitalized interest, foreign exchange adjustments, and principal repayments. (3) Considered to be transferred at the end of the period. Transfers into Level 3 occur when observable inputs are no longer available. Transfers out of Level 3 occur when observable inputs become available. The following table presents transfers in and out of each of the valuation levels of fair values. Six Months Ended June 30, 2018 2017 In Out Net In Out Net Level 1 $ — $ — $ 4 $ (597 ) $ (593 ) Level 2 — — — 597 (4 ) 593 Level 3 — — — — — — Fair Value Option : As discussed in Note 2—New Accounting Standards , the Company elected the fair value option in the first quarter of 2018, subsequent to the adoption of ASU 2016-01, to record its investment in certain limited partnerships at fair value with changes recognized in "Realized Investment Gains (Losses)" in the Condensed Consolidated Statements of Operations in accordance with ASC 825 . Distributions received on a semi-annual basis are recorded in Net Investment Income. The limited partnerships are recorded in Other Long-Term Investments on the Condensed Consolidated Balance Sheets . The following table represents the fair value of investments elected for the fair value option method measured on a recurring basis at June 30, 2018 , and the changes in fair value for the six months ended June 30, 2018 . Fair Value Measurements at June 30, 2018 Changes in Fair Values for the Period for Items Measured at Fair Value Pursuant to Election of the Fair Value Option Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs Total Fair Value Net Gains and Losses Recognized During the Period Less Net Gains and Losses Recognized due to Sales Total Changes in Fair Values Included in Current-Period Earnings Limited partnerships $ — $ 108,452 $ — $ 108,452 $ 2,861 $ — $ 2,861 Other-Than-Temporary Impairments : In accordance with the other-than-temporary impairment (OTTI) policy, the Company evaluated its fixed maturities available for sale in an unrealized loss position to determine if there was any impairment for the quarter. Gross unrealized losses may fluctuate quarter over quarter due to adverse factors in the market that affect our holdings, such as changes in the interest rates or credit spreads. While the Company holds securities that may be in an unrealized loss position from time to time, Torchmark has the ability and intent to hold these investments to recovery. Additionally, Torchmark does not expect to be required to sell any of its securities due to the strong cash flows generated by its insurance operations. For the three and six months ended June 30, 2018 , the Company concluded that there were no other-than-temporary impairments. For the comparable period in 2017 , the Company recorded $245 thousand ( $159 thousand , net of tax) in OTTI. Unrealized Loss Analysis : The following table discloses information about fixed maturities available for sale in an unrealized loss position. Less than Twelve Months Twelve Months or Longer Total Number of issues (CUSIP numbers) held: As of June 30, 2018 489 99 588 As of December 31, 2017 92 102 194 Torchmark’s entire fixed maturity portfolio consisted of 1,532 issues at June 30, 2018 and 1,502 issues at December 31, 2017 . The weighted average quality rating of all unrealized loss positions as of June 30, 2018 was BBB+ compared with BBB- as of December 31, 2017 . The following tables disclose unrealized investment losses by class and major sector of fixed maturities available for sale at June 30, 2018 and December 31, 2017 for the respective periods of time in a loss position. Torchmark considers these investments to be only temporarily impaired. Analysis of Gross Unrealized Investment Losses At June 30, 2018 Less than Twelve Months Twelve Months or Longer Total Description of Securities Fair Value Unrealized Loss Fair Unrealized Loss Fair Unrealized Loss Fixed maturities available for sale: Investment grade securities: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 172,110 $ (3,061 ) $ 38,389 $ (1,322 ) $ 210,499 $ (4,383 ) States, municipalities and political subdivisions 35,311 (268 ) 1,190 (13 ) 36,501 (281 ) Corporates, by sector: Financial 816,233 (29,495 ) 53,487 (3,995 ) 869,720 (33,490 ) Utilities 292,562 (10,578 ) 31,417 (1,501 ) 323,979 (12,079 ) Energy 221,851 (10,100 ) 49,555 (7,078 ) 271,406 (17,178 ) Other corporate sectors 2,462,504 (109,374 ) 154,756 (19,286 ) 2,617,260 (128,660 ) Total corporates 3,793,150 (159,547 ) 289,215 (31,860 ) 4,082,365 (191,407 ) Other asset-backed securities 36,920 (429 ) — — 36,920 (429 ) Redeemable preferred stocks, by sector: Financial 10,127 (680 ) — — 10,127 (680 ) Utilities — — 5,667 (356 ) 5,667 (356 ) Total redeemable preferred stocks 10,127 (680 ) 5,667 (356 ) 15,794 (1,036 ) Total investment grade securities 4,047,618 (163,985 ) 334,461 (33,551 ) 4,382,079 (197,536 ) Below investment grade securities: Corporates, by sector: Financial 26,070 (4,704 ) 61,706 (13,251 ) 87,776 (17,955 ) Utilities 15,098 (85 ) — — 15,098 (85 ) Energy 26,166 (1,010 ) 67,777 (21,913 ) 93,943 (22,923 ) Other corporate sectors 78,721 (7,108 ) 52,397 (10,795 ) 131,118 (17,903 ) Total corporates 146,055 (12,907 ) 181,880 (45,959 ) 327,935 (58,866 ) Collateralized debt obligations — — 14,177 (5,823 ) 14,177 (5,823 ) Redeemable preferred stocks, by sector: Financial — — 23,252 (3,838 ) 23,252 (3,838 ) Total redeemable preferred stocks — — 23,252 (3,838 ) 23,252 (3,838 ) Total below investment grade securities 146,055 (12,907 ) 219,309 (55,620 ) 365,364 (68,527 ) Total fixed maturities $ 4,193,673 $ (176,892 ) $ 553,770 $ (89,171 ) $ 4,747,443 $ (266,063 ) Analysis of Gross Unrealized Investment Losses At December 31, 2017 Less than Twelve Months Twelve Months or Longer Total Description of Securities Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Fixed maturities available for sale: Investment grade securities: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 34,388 $ (422 ) $ 47,514 $ (951 ) $ 81,902 $ (1,373 ) States, municipalities and political subdivisions 4,561 (21 ) 1,771 (9 ) 6,332 (30 ) Corporates, by sector: Financial 133,080 (652 ) 35,302 (1,429 ) 168,382 (2,081 ) Utilities 48,562 (569 ) 32,345 (729 ) 80,907 (1,298 ) Energy 23,463 (81 ) 67,775 (3,682 ) 91,238 (3,763 ) Other corporate sectors 220,661 (2,312 ) 163,886 (4,257 ) 384,547 (6,569 ) Total corporates 425,766 (3,614 ) 299,308 (10,097 ) 725,074 (13,711 ) Redeemable preferred stocks, by sector: Utilities — — 5,953 (97 ) 5,953 (97 ) Total redeemable preferred stocks — — 5,953 (97 ) 5,953 (97 ) Total investment grade securities 464,715 (4,057 ) 354,546 (11,154 ) 819,261 (15,211 ) Below investment grade securities: States, municipalities and political subdivisions 200 (105 ) — — 200 (105 ) Corporates, by sector: Financial — — 84,432 (21,311 ) 84,432 (21,311 ) Energy 8,114 (104 ) 75,204 (21,525 ) 83,318 (21,629 ) Other corporate sectors 25,334 (5,066 ) 54,383 (8,981 ) 79,717 (14,047 ) Total corporates 33,448 (5,170 ) 214,019 (51,817 ) 247,467 (56,987 ) Collateralized debt obligations — — 12,347 (7,653 ) 12,347 (7,653 ) Redeemable preferred stocks, by sector: Financial — — 24,376 (2,727 ) 24,376 (2,727 ) Total redeemable preferred stocks — — 24,376 (2,727 ) 24,376 (2,727 ) Total below investment grade securities 33,648 (5,275 ) 250,742 (62,197 ) 284,390 (67,472 ) Total fixed maturities $ 498,363 $ (9,332 ) $ 605,288 $ (73,351 ) $ 1,103,651 $ (82,683 )

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes In 2017, the newly enacted tax legislation revised the corporate income tax rate from 35% to 21% effective January 1, 2018. The change in tax rates was the primary reason for the difference in the Company’s effective tax rate as compared with the prior year periods. The effective income tax rate differed from the expected rate for the three and six month periods ended June 30, 2018 and 2017 as shown below: Three Months Ended June 30, 2018 % 2017 % Expected income taxes $ 47,641 21.0 $ 70,674 35.0 Increase (reduction) in income taxes resulting from: Low income housing investments (3,324 ) (1.5 ) (4,649 ) (2.3 ) Share-based awards (2,055 ) (0.9 ) (4,018 ) (2.0 ) Other 209 0.1 (444 ) (0.2 ) Income tax expense (benefit) from continuing operations $ 42,471 18.7 $ 61,563 30.5 Six Months Ended June 30, 2018 % 2017 % Expected income taxes $ 92,338 21.0 $ 137,783 35.0 Increase (reduction) in income taxes resulting from: Low income housing investments (6,649 ) (1.5 ) (9,298 ) (2.4 ) Share-based awards (4,254 ) (1.0 ) (9,439 ) (2.4 ) Other 167 — (2,920 ) (0.7 ) Income tax expense (benefit) from continuing operations $ 81,602 18.5 $ 116,126 29.5 As of December 31, 2017, the Company recorded $877 million of tax benefits in net income as a result of remeasuring its deferred tax assets and liabilities using the lower corporate tax rate as of the legislation’s enactment date. The Company was able to determine that the adjustment recorded in 2017 was a reasonable estimate of the impact of the tax legislation in accordance with SAB 118. The guidance allows companies up to one year to finalize the impact. The Company did not make any adjustments to this estimate for the period ended June 30, 2018 . However, the Company will continue to analyze relevant information to complete the accounting for income taxes and expects to complete the process in the fourth quarter of 2018.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation : Torchmark and its subsidiaries, in common with the insurance industry in general, are subject to litigation, involving various matters where we are either the defendant or the plaintiff. Torchmark subsidiaries are also currently the subject of audits regarding the identification, reporting and escheatment of unclaimed property arising from life insurance policies and a limited number of annuity contracts. In each of these matters, based upon information presently available, management does not believe that such litigation or audits will have a material adverse effect on Torchmark’s financial condition, future operating results or liquidity. On February 1, 2018, putative class action litigation was filed against American Income Life Insurance Company in U.S. District Court for the Northern District of Texas, Dallas Division ( Bruce v. American Income Life Insurance Company, et al. , Case No. 3:18-cv-00258-G). The plaintiff, a former insurance sales agent of American Income who is suing on behalf of all current and former American Income sales agents contracted through State General Agent Stephen Jubrey’s agency office at any time since January 31, 2015 through the final disposition of this matter, asserts that such agents are employees rather than independent contractors as they are classified by American Income. He alleges failure to pay minimum wages, overtime wages and other applicable monies in accordance with the Fair Labor Standards Act. The plaintiff seeks, in a jury trial, actual and punitive damages, pre- and post-judgment interest, attorney fees, costs and other relief, including injunctive relief. On February 27, 2018, the Company filed a motion to compel arbitration of this matter and on July 27, 2018, the Court granted the Company’s motion. With respect to current litigation, at this time management believes that the possibility of a material judgment adverse to Torchmark is remote, and no estimate of range can be made for loss contingencies that are at least reasonably possible but not accrued. Guarantees: Torchmark has guaranteed letters of credit in connection with its credit facility with a group of banks. The letters of credit were issued by TMK Re, Ltd., a wholly-owned subsidiary, to secure TMK Re, Ltd.’s obligation for claims on certain policies reinsured by TMK Re, Ltd. that were sold by other Torchmark insurance companies. These letters of credit facilitate TMK Re, Ltd.’s ability to reinsure the business of Torchmark’s insurance carriers. The agreement expires in 2021. The maximum amount of letters of credit available is $250 million . Torchmark would be liable to the extent that TMK Re, Ltd. does not pay the reinsured party. On March 14, 2018, the letters of credit were amended to reduce the current amount outstanding to $155 million from $177 million as of December 31, 2017.

Liability for Unpaid Claims

Liability for Unpaid Claims	6 Months Ended
	Jun. 30, 2018
Insurance [Abstract]
Liability for Unpaid Claims	Liability for Unpaid Claims Activity in the liability for unpaid health claims is summarized as follows: Six Months Ended 2018 2017 Balance at beginning of period $ 146,865 $ 143,128 Incurred related to: Current year 269,574 264,648 Prior years (5,708 ) (8,364 ) Total incurred 263,866 256,284 Paid related to: Current year 171,199 164,271 Prior years 99,054 94,676 Total paid 270,253 258,947 Balance at end of period $ 140,478 $ 140,465 Below is the reconciliation of the liability for "Policy claims and other benefits payable" in the Condensed Consolidated Balance Sheets . June 30, December 31, 2017 Policy claims and other benefits payable: Life insurance $ 188,991 $ 186,429 Health insurance 140,478 146,865 Total $ 329,469 $ 333,294

Postretirement Benefits

Postretirement Benefits	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
Postretirement Benefits	Postretirement Benefits The following tables present a summary of post-retirement benefit costs by component for the three and six month periods ended June 30, 2018 and 2017 . Components of Post-Retirement Benefit Costs Three Months Ended June 30, Pension Benefits Other Benefits 2018 2017 2018 2017 Service cost $ 5,277 $ 4,484 $ — $ — Interest cost 5,493 5,551 228 250 Expected return on assets (6,363 ) (5,898 ) — — Amortization: Prior service cost 119 119 — — Actuarial (gain) loss 3,636 2,952 23 38 Direct recognition of expense — — 85 116 Net periodic benefit cost $ 8,162 $ 7,208 $ 336 $ 404 Six Months Ended June 30, Pension Benefits Other Benefits 2018 2017 2018 2017 Service cost $ 10,554 $ 8,971 $ — $ — Interest cost 10,986 11,101 456 500 Expected return on assets (12,726 ) (11,797 ) — — Amortization: Prior service cost 238 238 — — Actuarial (gain)/loss 7,272 5,903 46 77 Direct recognition of expense — — 225 212 Net periodic benefit cost $ 16,324 $ 14,416 $ 727 $ 789 The following tables present the assets of Torchmark’s defined benefit pension plans at June 30, 2018 and December 31, 2017 . Pension Assets by Component at June 30, 2018 Fair Value Determined by: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Amount % to Total Corporate bonds: Financial $ $ 46,501 $ $ 46,501 12 Utilities 40,032 40,032 10 Energy 23,551 23,551 6 Other corporates 67,960 67,960 17 Total corporate bonds — 178,044 — 178,044 45 Exchange traded fund (1) 168,743 168,743 43 Other bonds 245 245 — Other long-term investments 3,998 3,998 1 Guaranteed annuity contract (2) 21,427 21,427 5 Short-term investments 18,660 18,660 5 Other 1,866 1,866 1 Grand Total $ 189,269 $ 203,714 $ — $ 392,983 100 (1) A fund including marketable securities that mirror the S&P 500 index. (2) Representing a guaranteed annuity contract issued by Torchmark's subsidiary, American Income Life Insurance Company, to fund the obligations of the American Income Pension Plan. Pension Assets by Component at December 31, 2017 Fair Value Determined by: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Amount % to Total Corporate bonds: Financial $ $ 43,451 $ $ 43,451 12 Utilities 46,144 46,144 12 Energy 25,023 25,023 7 Other corporates 65,888 65,888 17 Total corporate bonds — 180,506 — 180,506 48 Exchange traded fund (1) 164,351 164,351 43 Other bonds 256 256 — Other long-term investments 2,304 2,304 1 Guaranteed annuity contract (2) 21,202 21,202 6 Short-term investments 3,984 3,984 1 Other 5,021 5,021 1 Grand Total $ 173,356 $ 204,268 $ — $ 377,624 100 (1) A fund including marketable securities that mirror the S&P 500 index. (2) Representing a guaranteed annuity contract issued by Torchmark's subsidiary, American Income Life Insurance Company, to fund the obligations of the American Income Pension Plan. The following table presents liabilities for the defined-benefit pension plans at June 30, 2018 and December 31, 2017 . Pension Liability June 30, December 31, 2017 Funded defined benefit pension $ 509,965 $ 518,141 SERPs (1) 85,382 84,465 Pension Benefit Obligation $ 595,347 $ 602,606 (1) Supplemental executive retirement plan (SERP). The following table includes information regarding the SERPs at June 30, 2018 and December 31, 2017 . June 30, December 31, 2017 Premiums paid for insurance coverage $ 1,047 $ 2,050 Total investments: Company owned life insurance $ 41,872 $ 40,273 Exchange traded funds 55,051 55,442 $ 96,923 $ 95,715 Liability: Active plan $ 82,862 $ 81,457 Closed plan 2,520 3,008 $ 85,382 $ 84,465

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share A reconciliation of basic and diluted weighted-average shares outstanding is as follows: Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Basic weighted average shares outstanding 113,350,175 116,646,669 113,762,340 117,205,467 Weighted average dilutive options outstanding 2,301,237 2,449,882 2,434,633 2,554,158 Diluted weighted average shares outstanding 115,651,412 119,096,551 116,196,973 119,759,625 Antidilutive shares 1,381,686 1,444,280 960,753 1,037,328

Business Segments

Business Segments	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Business Segments	Business Segments Torchmark's reportable segments are based on the insurance product lines it markets and administers: life insurance, health insurance, and annuities. These major product lines are set out as reportable segments because of the common characteristics of products within these categories, comparability of margins, and the similarity in regulatory environment and management techniques. Torchmark's chief operating decision makers evaluate the overall performance of the operations of the Company in accordance with these segments. Management’s measure of profitability for each insurance segment is insurance underwriting margin, which is underwriting income before other income and insurance administrative expenses. It represents the profit margin on insurance products before administrative expenses, and is calculated by deducting net policy obligations (claims incurred and change in reserves), commissions and other acquisition expenses from premium revenue. Torchmark further views the profitability of each insurance product segment by the marketing groups that distribute the products of that segment: direct response, independent agencies, or captive agencies. Torchmark’s management prefers to evaluate the performance of its underwriting and investment activities separately, rather than allocating investment income to the underwriting results. As such, the investment function is presented as a stand-alone segment. The investment segment includes the management of the investment portfolio, debt, and cash flow. Management’s measure of profitability for this segment is excess investment income, which is the income earned on the investment portfolio less the required interest on net policy liabilities and financing costs. Financing costs include the interest on Torchmark’s debt. Other income and insurance administrative expense are classified in a separate Corporate and other segment. The majority of the Company’s required interest on net policy liabilities (benefit reserves less the deferred acquisition cost asset) is not credited to policyholder accounts. Instead, it is an actuarial assumption for discounting cash flows in the computation of benefit reserves and the amortization of the deferred acquisition cost asset. Investment income required to fund the required interest on net policy liabilities is removed from the investment segment and applied to the insurance segments to eliminate the effect of the required interest from the insurance segments. As a result, the investment segment measures net investment income against the required interest on net policy liabilities and financing costs, while the insurance segments simply measure premiums against net policy benefits and expenses. Management believes this presentation facilitates a more meaningful analysis of the Company’s underwriting and investment performance as the underwriting results are based on premiums, claims, and expenses and are not affected by unanticipated fluctuations in investment yields. As noted, Torchmark’s core operations are insurance and investment management. The insurance segments issue policies for which premiums are collected for the eventual payment of policy benefits. In addition to policy benefits, operating expenses are incurred including acquisition costs, administrative expenses, and taxes. Because life and health contracts can be long term, premium receipts in excess of current expenses are invested. Investment activities, conducted by the investment segment, focus on seeking quality investments with a yield and term appropriate to support the insurance product obligations. These investments generally consist of fixed maturities, and, over the long term, the expected yields are taken into account when setting insurance premium rates and product profitability expectations. As a result, fixed maturities are generally held for long periods to support the liabilities, and Torchmark generally expects to hold investments until maturity. However, dispositions of investments occur from time to time, generally for reasons such as credit concerns, calls by issuers, or other factors. Since Torchmark does not actively trade investments, realized gains and losses from the disposition and write down of investments are generally incidental to operations and are not considered a material factor in insurance pricing or product profitability. While from time to time these realized gains and losses could be significant to net income in the period in which they occur, they generally have a limited effect on the yield of the total investment portfolio. Further, the disposals have little effect on the size of the portfolio as the proceeds of the disposals are reinvested in the portfolio and the income from the reinvestments is included in net investment income. Therefore, management removes realized investment gains and losses from results of core operations when evaluating the performance of the Company. For this reason, these gains and losses are excluded from Torchmark’s operating segments. Torchmark accounts for its stock options and restricted stock under current accounting guidance requiring stock options and stock grants to be expensed based on fair value at the time of grant. Management considers stock compensation expense to be an expense of the Parent Company. Therefore, stock compensation expense is treated as a corporate expense in Torchmark’s segment analysis. The following tables set forth a reconciliation of Torchmark’s revenues and operations by segment to its pre-tax income and each significant line item in its Condensed Consolidated Statements of Operations . Reconciliation of Segment Operating Information to the Condensed Consolidated Statement of Operations Three Months Ended June 30, 2018 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 602,534 $ 251,440 $ 5 $ 853,979 Net investment income $ 218,568 218,568 Other income $ 441 $ (25 ) (2) 416 Total revenue 602,534 251,440 5 218,568 441 (25 ) 1,072,963 Expenses: Policy benefits 399,334 160,461 8,582 568,377 Required interest on reserves (158,101 ) (20,726 ) (11,885 ) 190,712 — Required interest on DAC 48,275 6,079 150 (54,504 ) — Amortization of acquisition costs 104,599 23,892 586 129,077 Commissions, premium taxes, and non-deferred acquisition costs 47,250 22,196 6 (25 ) (2) 69,427 Insurance administrative expense (1) 55,276 55,276 Parent expense 2,847 2,847 Stock-based compensation expense 10,497 10,497 Interest expense 22,411 22,411 Total expenses 441,357 191,902 (2,561 ) 158,619 68,620 (25 ) 857,912 Subtotal 161,177 59,538 2,566 59,949 (68,179 ) — 215,051 Non-operating items — — Measure of segment profitability (pretax) $ 161,177 $ 59,538 $ 2,566 $ 59,949 $ (68,179 ) $ — 215,051 Deduct applicable income taxes (39,991 ) Net operating income 175,060 Add back income taxes applicable to segment profitability 39,991 Add (deduct) realized investment gains (losses) 11,813 Income before income taxes per Condensed Consolidated Statement of Operations $ 226,864 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. Three Months Ended June 30, 2017 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 573,836 $ 242,775 $ 3 $ 816,614 Net investment income $ 212,776 212,776 Other income $ 427 $ (34 ) (2) 393 Total revenue 573,836 242,775 3 212,776 427 (34 ) 1,029,783 Expenses: Policy benefits 388,765 156,579 8,977 2,094 (3) 556,415 Required interest on reserves (150,652 ) (19,267 ) (12,394 ) 182,313 — Required interest on DAC 46,213 5,840 174 (52,227 ) — Amortization of acquisition costs 98,473 23,016 632 122,121 Commissions, premium taxes, and non-deferred acquisition costs 43,708 21,351 7 (34 ) (2) 65,032 Insurance administrative expense (1) 51,412 51,412 Parent expense 2,665 2,665 Stock-based compensation expense 8,351 8,351 Interest expense 21,156 21,156 Total expenses 426,507 187,519 (2,604 ) 151,242 62,428 2,060 827,152 Subtotal 147,329 55,256 2,607 61,534 (62,001 ) (2,094 ) 202,631 Non-operating items 2,094 (3) 2,094 Measure of segment profitability (pretax) $ 147,329 $ 55,256 $ 2,607 $ 61,534 $ (62,001 ) $ — 204,725 Deduct applicable income taxes (62,543 ) Net operating income 142,182 Add back income taxes applicable to segment profitability 62,543 Add (deduct) realized investment gains (losses) (705 ) Add (deduct) administrative settlements (3) (2,094 ) Income before income taxes per Condensed Consolidated Statement of Operations $ 201,926 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. (3) Administrative settlements. Six Months Ended June 30, 2018 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 1,200,837 $ 503,238 $ 10 $ 1,704,085 Net investment income $ 436,652 436,652 Other income $ 764 $ (53 ) (2) 711 Total revenue 1,200,837 503,238 10 436,652 764 (53 ) 2,141,448 Expenses: Policy benefits 799,915 321,080 17,271 1,138,266 Required interest on reserves (314,315 ) (41,130 ) (23,902 ) 379,347 — Required interest on DAC 96,219 12,092 303 (108,614 ) — Amortization of acquisition costs 208,376 49,149 1,172 258,697 Commissions, premium taxes, and non-deferred acquisition costs 94,644 44,461 14 (53 ) (2) 139,066 Insurance administrative expense (1) 110,748 110,748 Parent expense 5,139 5,139 Stock-based compensation expense 19,557 19,557 Interest expense 44,033 44,033 Total expenses 884,839 385,652 (5,142 ) 314,766 135,444 (53 ) 1,715,506 Subtotal 315,998 117,586 5,152 121,886 (134,680 ) — 425,942 Non-operating items — — Measure of segment profitability (pretax) $ 315,998 $ 117,586 $ 5,152 $ 121,886 $ (134,680 ) $ — 425,942 Deduct applicable income taxes (78,712 ) Net operating income 347,230 Add back income taxes applicable to segment profitability 78,712 Add (deduct) realized investment gains (losses) 13,764 Income before income taxes per Condensed Consolidated Statements of Operations $ 439,706 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. Six Months Ended June 30, 2017 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 1,149,673 $ 487,566 $ 6 $ 1,637,245 Net investment income $ 421,058 421,058 Other income $ 878 $ (69 ) (2) 809 Total revenue 1,149,673 487,566 6 421,058 878 (69 ) 2,059,112 Expenses: Policy benefits 779,844 314,330 17,923 2,094 (3) 1,114,191 Required interest on reserves (299,477 ) (38,242 ) (24,812 ) 362,531 — Required interest on DAC 92,149 11,649 352 (104,150 ) — Amortization of acquisition costs 198,378 48,343 1,308 248,029 Commissions, premium taxes, and non-deferred acquisition costs 87,346 42,853 18 (69 ) (2) 130,148 Insurance administrative expense (1) 103,325 103,325 Parent expense 4,898 4,898 Stock-based compensation expense 16,546 16,546 Interest expense 41,855 41,855 Total expenses 858,240 378,933 (5,211 ) 300,236 124,769 2,025 1,658,992 Subtotal 291,433 108,633 5,217 120,822 (123,891 ) (2,094 ) 400,120 Non-operating items 2,094 (3) 2,094 Measure of segment profitability (pretax) $ 291,433 $ 108,633 $ 5,217 $ 120,822 $ (123,891 ) $ — 402,214 Deduct applicable income taxes (121,361 ) Net operating income 280,853 Add back income taxes applicable to segment profitability 121,361 Add (deduct) realized investment gains (losses) (6,453 ) Add (deduct) administrative settlements (3) (2,094 ) Income before income taxes per Condensed Consolidated Statements of Operations $ 393,667 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. (3) Administrative settlements.

Significant Accounting Polici19

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2018
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 June 30, 2018 , and the condensed consolidated results of operations, comprehensive income, and cash flows for the periods ended June 30, 2018 and 2017 . 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 26, 2018.
Accounting Pronouncements Adopted / Not Yet Adopted	Accounting Pronouncements Adopted in the Current Year: 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, the guidance 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 or equity method. This standard became effective for the Company on January 1, 2018. On January 1, 2018, the Company adopted this standard on a modified retrospective basis for two types of investments: equity securities and limited partnerships. The adoption resulted in a $4.9 million after tax positive adjustment to the opening balance of retained earnings. Subsequent to the adoption, the Company elected to measure its investment in certain limited partnerships at fair value in accordance with the fair value option for financial instruments with changes recognized in "Realized Investment Gains (Losses)" in the Condensed Consolidated Statements of Operations . As of June 30, 2018 , the fair value balance of the limited partnerships were $108 million . See Note 4—Investments for further discussion. 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 became effective on January 1, 2018 and did not have a significant impact to the classification on the Condensed Statement of Cash Flows . 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 guidance is applied on a modified retrospective approach and became effective on January 1, 2018. This adoption did 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 became 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 will record approximately $3.5 million in additional expense to the 2018 Condensed Consolidated Statements of Operations due to the elimination of the ability to capitalize a portion of the benefit costs. For the six months ended June 30, 2018 , the Company recorded $1.6 million in additional expense. 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 became effective on January 1, 2018. The adoption had no significant impact on the financial statements as modifications to stock compensation are infrequent. ASU 2018-02 : In February 2018, the FASB issued ASU No. 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (AOCI) . This guidance was issued to allow the reclassification of taxes from AOCI to retained earnings as a result of the reduction in corporate income tax rates due to the Tax Cuts and Jobs Act of 2017 (Tax Legislation). Current accounting requires the effect of changes in tax rates used to measure deferred tax assets and liabilities to be reported in net income as of the date of enactment even though deferred taxes were previously recognized in AOCI (stranded taxes). This guidance, however, allows a company to elect to reclassify the stranded taxes in AOCI to retained earnings and is effective for years beginning after December 15, 2018, with early adoption permitted. The Company elected to early adopt this guidance resulting in a reclassification of $252 million from AOCI to retained earnings for the period ended December 31, 2017. Accounting Pronouncements Not Yet Adopted ASU 2016-02/ASU 2018-11: In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), with clarification guidance issued in July 2018. The guidance requires lessees to record a right-of-use asset and corresponding lease liability on the balance sheet for all operating leases that do not qualify for the practical expedients allowed for in this standard. Additional qualitative and quantitative disclosures will be required. This standard will become effective for the Company beginning January 1, 2019. The Company plans to adopt the transition method allowed for under ASU 2018-11 and will not restate comparative periods upon adoption. Early adoption is permitted. The Company does not expect the adoption to have a significant impact on the financial statements. Refer to Note 15—Commitments and Contingencies of the 2017 10-K for consideration of the noncancelable operating lease commitments. The Company is not a lessor. 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 by use of an allowance rather than a direct write-down. 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 current available-for-sale portfolio. 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 an impact to the financial statements. 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.

Supplemental Information abou20

Supplemental Information about Changes to Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Schedule of Analysis of Change in Balance by Component of Accumulated Other Comprehensive Income	An analysis of the change in balance by component of Accumulated Other Comprehensive Income is as follows for the three and six month periods ended June 30, 2018 and 2017 . Components of Accumulated Other Comprehensive Income Three Months Ended June 30, 2017 Available Deferred Foreign Pension Total Balance at April 1, 2017 $ 832,057 $ (7,182 ) $ 8,753 $ (110,763 ) $ 722,865 Other comprehensive income (loss) before reclassifications, net of tax 257,595 (473 ) 2,149 — 259,271 Reclassifications, net of tax 403 — — 2,021 2,424 Other comprehensive income (loss) 257,998 (473 ) 2,149 2,021 261,695 Balance at June 30, 2017 $ 1,090,055 $ (7,655 ) $ 10,902 $ (108,742 ) $ 984,560 Three Months Ended June 30, 2018 Available Deferred Foreign Pension Total Balance at April 1, 2018 $ 1,082,896 $ (8,191 ) $ 15,279 $ (149,785 ) $ 940,199 Other comprehensive income (loss) before reclassifications, net of tax (329,619 ) 1,612 (4,914 ) — (332,921 ) Reclassifications, net of tax (6,763 ) — — 2,984 (3,779 ) Other comprehensive income (loss) (336,382 ) 1,612 (4,914 ) 2,984 (336,700 ) Balance at June 30, 2018 $ 746,514 $ (6,579 ) $ 10,365 $ (146,801 ) $ 603,499 Six Months Ended June 30, 2017 Available Deferred Foreign Pension Total Balance at January 1, 2017 $ 692,314 $ (6,682 ) $ 4,967 $ (113,025 ) $ 577,574 Other comprehensive income (loss) before reclassifications, net of tax 398,295 (973 ) 5,935 241 403,498 Reclassifications, net of tax (554 ) — — 4,042 3,488 Other comprehensive income (loss) 397,741 (973 ) 5,935 4,283 406,986 Balance at June 30, 2017 $ 1,090,055 $ (7,655 ) $ 10,902 $ (108,742 ) $ 984,560 Six Months Ended June 30, 2018 Available Deferred Foreign Pension Total Balance at January 1, 2018 $ 1,569,289 $ (8,547 ) $ 16,302 $ (152,770 ) $ 1,424,274 Other comprehensive income (loss) before reclassifications, net of tax (815,462 ) 1,968 (5,937 ) — (819,431 ) Reclassifications, net of tax (7,313 ) — — 5,969 (1,344 ) Other comprehensive income (loss) (822,775 ) 1,968 (5,937 ) 5,969 (820,775 ) Balance at June 30, 2018 $ 746,514 $ (6,579 ) $ 10,365 $ (146,801 ) $ 603,499
Summary of Reclassifications Out of Accumulated Other Comprehensive Income	Reclassifications out of Accumulated Other Comprehensive Income are presented below for the three and six month periods ended June 30, 2018 and 2017 . Reclassification Adjustments Three Months Ended Six Months Ended Affected line items in the Statement of Operations 2018 2017 2018 2017 Unrealized investment gains (losses) on available for sale assets: Realized (gains) losses $ (9,431 ) $ 681 $ (10,817 ) $ (354 ) Realized investment gains (losses) Amortization of (discount) premium 870 (61 ) 1,560 (498 ) Net investment income Total before tax (8,561 ) 620 (9,257 ) (852 ) Tax 1,798 (217 ) 1,944 298 Income taxes Total after tax (6,763 ) 403 (7,313 ) (554 ) Pension adjustments: Amortization of prior service cost 119 119 238 238 Other operating expense Amortization of actuarial gain (loss) 3,659 2,990 7,318 5,980 Other operating expense Total before tax 3,778 3,109 7,556 6,218 Tax (794 ) (1,088 ) (1,587 ) (2,176 ) Income taxes Total after tax 2,984 2,021 5,969 4,042 Total reclassifications (after tax) $ (3,779 ) $ 2,424 $ (1,344 ) $ 3,488

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Summary of Fixed Maturities and Equity Securities Available for Sale by Cost or Amortized Cost and Estimated Fair Value	A summary of fixed maturities available for sale by cost or amortized cost and estimated fair value at June 30, 2018 and December 31, 2017 is as follows: June 30, 2018 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (1) % of Total Fixed Maturities (2) Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 390,021 $ 2,266 $ (4,383 ) $ 387,904 2 States, municipalities, and political subdivisions 1,232,142 103,365 (281 ) 1,335,226 9 Foreign governments 19,609 1,705 — 21,314 — Corporates, by sector: Financial 3,372,221 269,494 (51,445 ) 3,590,270 22 Utilities 1,947,899 255,504 (12,164 ) 2,191,239 14 Energy 1,619,674 133,584 (40,101 ) 1,713,157 11 Other corporate sectors 6,183,619 362,020 (146,563 ) 6,399,076 39 Total corporates 13,123,413 1,020,602 (250,273 ) 13,893,742 86 Collateralized debt obligations 58,582 23,437 (5,823 ) 76,196 — Other asset-backed securities 150,843 2,386 (429 ) 152,800 1 Redeemable preferred stocks, by sector: Financial 347,014 45,481 (4,518 ) 387,977 2 Utilities 28,528 1,360 (356 ) 29,532 — Total redeemable preferred stocks 375,542 46,841 (4,874 ) 417,509 2 Total fixed maturities $ 15,350,152 $ 1,200,602 $ (266,063 ) $ 16,284,691 100 (1) Amounts reported on the balance sheet. (2) At fair value. December 31, 2017 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (1) % of Total Fixed Maturities (2) Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 390,646 $ 18,173 $ (1,373 ) $ 407,446 2 States, municipalities, and political subdivisions 1,091,960 127,890 (135 ) 1,219,715 7 Foreign governments 20,236 1,782 — 22,018 — Corporates, by sector: Financial 3,282,526 475,961 (23,392 ) 3,735,095 22 Utilities 1,955,737 369,406 (1,298 ) 2,323,845 14 Energy 1,619,349 226,140 (25,392 ) 1,820,097 11 Other corporate sectors 6,065,803 747,612 (20,616 ) 6,792,799 40 Total corporates 12,923,415 1,819,119 (70,698 ) 14,671,836 87 Collateralized debt obligations 59,150 20,084 (7,653 ) 71,581 — Other asset-backed securities 144,520 4,835 — 149,355 1 Redeemable preferred stocks, by sector: Financial 336,621 62,892 (2,727 ) 396,786 3 Utilities 28,553 2,132 (97 ) 30,588 — Total redeemable preferred stocks 365,174 65,024 (2,824 ) 427,374 3 Total fixed maturities $ 14,995,101 $ 2,056,907 $ (82,683 ) $ 16,969,325 100 (1) Amounts reported on the balance sheet. (2) At fair value.
Schedule of Fixed Maturities by Contractual Maturity Date	A schedule of fixed maturities available for sale by contractual maturity date at June 30, 2018 is shown below on an amortized cost basis and on a fair value basis. Actual disposition dates could differ from contractual maturities due to call or prepayment provisions. June 30, 2018 Amortized Fair Value Fixed maturities available for sale: Due in one year or less $ 80,564 $ 81,901 Due after one year through five years 732,395 757,040 Due after five years through ten years 1,611,476 1,745,491 Due after ten years through twenty years 5,051,297 5,607,509 Due after twenty years 7,664,183 7,862,890 Mortgage-backed and asset-backed securities 210,237 229,860 $ 15,350,152 $ 16,284,691
Schedule of Assets Measured at Fair Value on Recurring Basis	The following tables represents the fair value of fixed maturities available for sale measured on a recurring basis at June 30, 2018 and December 31, 2017 . Fair Value Measurements at June 30, 2018 using: Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ — $ 387,904 $ — $ 387,904 States, municipalities, and political subdivisions — 1,335,226 — 1,335,226 Foreign governments — 21,314 — 21,314 Corporates, by sector: Financial — 3,529,651 60,619 3,590,270 Utilities — 2,044,141 147,098 2,191,239 Energy — 1,673,305 39,852 1,713,157 Other corporate sectors — 6,069,835 329,241 6,399,076 Total corporates — 13,316,932 576,810 13,893,742 Collateralized debt obligations — — 76,196 76,196 Other asset-backed securities — 139,647 13,153 152,800 Redeemable preferred stocks, by sector: Financial — 387,977 — 387,977 Utilities — 29,532 — 29,532 Total redeemable preferred stocks — 417,509 — 417,509 Total fixed maturities $ — $ 15,618,532 $ 666,159 $ 16,284,691 Percent of total — % 95.9 % 4.1 % 100.0 % Fair Value Measurements at December 31, 2017 using: Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Fixed maturities available for sale: U.S. Government direct, guaranteed, and government-sponsored enterprises $ — $ 407,446 $ — $ 407,446 States, municipalities, and political subdivisions 44 1,219,671 — 1,219,715 Foreign governments — 22,018 — 22,018 Corporates, by sector: Financial — 3,673,089 62,006 3,735,095 Utilities — 2,168,115 155,730 2,323,845 Energy — 1,779,281 40,816 1,820,097 Other corporate sectors — 6,468,541 324,258 6,792,799 Total corporates — 14,089,026 582,810 14,671,836 Collateralized debt obligations — — 71,581 71,581 Other asset-backed securities — 135,306 14,049 149,355 Redeemable preferred stocks, by sector: Financial — 396,786 — 396,786 Utilities — 30,588 — 30,588 Total redeemable preferred stocks — 427,374 — 427,374 Total fixed maturities $ 44 $ 16,300,841 $ 668,440 $ 16,969,325 Percentage of total — % 96.1 % 3.9 % 100.0 %
Schedule of Analysis of Changes in Fair Value Measurements Using Significant Unobservable Inputs	The following tables represent an analysis of changes in fair value measurements using significant unobservable inputs (Level 3) for the six months ended June 30, 2018 and 2017 . Analysis of Changes in Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six Months Ended June 30, 2018 Asset- Collateralized Corporates (1) Total Balance at January 1, 2018 $ 14,049 $ 71,581 $ 582,810 $ 668,440 Total gains or losses: Included in realized gains/losses — — — — Included in other comprehensive income (697 ) 5,183 (19,611 ) (15,125 ) Acquisitions — — 20,300 20,300 Sales — — — — Amortization — 2,389 8 2,397 Other (2) (199 ) (2,957 ) (6,697 ) (9,853 ) Transfers in and/or out of Level 3 (3) — — — — Balance at June 30, 2018 $ 13,153 $ 76,196 $ 576,810 $ 666,159 Percent of total fixed maturities 0.1 % 0.5 % 3.5 % 4.1 % (1) Includes redeemable preferred stocks. (2) Includes capitalized interest, foreign exchange adjustments, and principal repayments. (3) Considered to be transferred at the end of the period. Transfers into Level 3 occur when observable inputs are no longer available. Transfers out of Level 3 occur when observable inputs become available. Six Months Ended June 30, 2017 Asset- Collateralized Corporates (1) Total Balance at January 1, 2017 $ — $ 63,503 $ 559,600 $ 623,103 Total gains or losses: Included in realized gains/losses — — — — Included in other comprehensive income 261 3,597 11,637 15,495 Acquisitions 14,000 — 21,666 35,666 Sales — — — — Amortization — 2,481 8 2,489 Other (2) (108 ) (3,336 ) (6,625 ) (10,069 ) Transfers in and/or out of Level 3 (3) — — — — Balance at June 30, 2017 $ 14,153 $ 66,245 $ 586,286 $ 666,684 Percent of total fixed maturities 0.1 % 0.4 % 3.6 % 4.1 % (1) Includes redeemable preferred stocks. (2) Includes capitalized interest, foreign exchange adjustments, and principal repayments. (3) Considered to be transferred at the end of the period. Transfers into Level 3 occur when observable inputs are no longer available. Transfers out of Level 3 occur when observable inputs become available.
Transfers In And Out Of Each Of Valuation Levels Of Fair Values	The following table presents transfers in and out of each of the valuation levels of fair values. Six Months Ended June 30, 2018 2017 In Out Net In Out Net Level 1 $ — $ — $ 4 $ (597 ) $ (593 ) Level 2 — — — 597 (4 ) 593 Level 3 — — — — — —
Fair Value of Investments Elected for the Fair Value Option	The following table represents the fair value of investments elected for the fair value option method measured on a recurring basis at June 30, 2018 , and the changes in fair value for the six months ended June 30, 2018 . Fair Value Measurements at June 30, 2018 Changes in Fair Values for the Period for Items Measured at Fair Value Pursuant to Election of the Fair Value Option Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs Total Fair Value Net Gains and Losses Recognized During the Period Less Net Gains and Losses Recognized due to Sales Total Changes in Fair Values Included in Current-Period Earnings Limited partnerships $ — $ 108,452 $ — $ 108,452 $ 2,861 $ — $ 2,861
Schedule of Information About Investments in Unrealized Loss Position	The following table discloses information about fixed maturities available for sale in an unrealized loss position. Less than Twelve Months Twelve Months or Longer Total Number of issues (CUSIP numbers) held: As of June 30, 2018 489 99 588 As of December 31, 2017 92 102 194
Schedule of Unrealized Investment Losses by Class of Investment	The following tables disclose unrealized investment losses by class and major sector of fixed maturities available for sale at June 30, 2018 and December 31, 2017 for the respective periods of time in a loss position. Torchmark considers these investments to be only temporarily impaired. Analysis of Gross Unrealized Investment Losses At June 30, 2018 Less than Twelve Months Twelve Months or Longer Total Description of Securities Fair Value Unrealized Loss Fair Unrealized Loss Fair Unrealized Loss Fixed maturities available for sale: Investment grade securities: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 172,110 $ (3,061 ) $ 38,389 $ (1,322 ) $ 210,499 $ (4,383 ) States, municipalities and political subdivisions 35,311 (268 ) 1,190 (13 ) 36,501 (281 ) Corporates, by sector: Financial 816,233 (29,495 ) 53,487 (3,995 ) 869,720 (33,490 ) Utilities 292,562 (10,578 ) 31,417 (1,501 ) 323,979 (12,079 ) Energy 221,851 (10,100 ) 49,555 (7,078 ) 271,406 (17,178 ) Other corporate sectors 2,462,504 (109,374 ) 154,756 (19,286 ) 2,617,260 (128,660 ) Total corporates 3,793,150 (159,547 ) 289,215 (31,860 ) 4,082,365 (191,407 ) Other asset-backed securities 36,920 (429 ) — — 36,920 (429 ) Redeemable preferred stocks, by sector: Financial 10,127 (680 ) — — 10,127 (680 ) Utilities — — 5,667 (356 ) 5,667 (356 ) Total redeemable preferred stocks 10,127 (680 ) 5,667 (356 ) 15,794 (1,036 ) Total investment grade securities 4,047,618 (163,985 ) 334,461 (33,551 ) 4,382,079 (197,536 ) Below investment grade securities: Corporates, by sector: Financial 26,070 (4,704 ) 61,706 (13,251 ) 87,776 (17,955 ) Utilities 15,098 (85 ) — — 15,098 (85 ) Energy 26,166 (1,010 ) 67,777 (21,913 ) 93,943 (22,923 ) Other corporate sectors 78,721 (7,108 ) 52,397 (10,795 ) 131,118 (17,903 ) Total corporates 146,055 (12,907 ) 181,880 (45,959 ) 327,935 (58,866 ) Collateralized debt obligations — — 14,177 (5,823 ) 14,177 (5,823 ) Redeemable preferred stocks, by sector: Financial — — 23,252 (3,838 ) 23,252 (3,838 ) Total redeemable preferred stocks — — 23,252 (3,838 ) 23,252 (3,838 ) Total below investment grade securities 146,055 (12,907 ) 219,309 (55,620 ) 365,364 (68,527 ) Total fixed maturities $ 4,193,673 $ (176,892 ) $ 553,770 $ (89,171 ) $ 4,747,443 $ (266,063 ) Analysis of Gross Unrealized Investment Losses At December 31, 2017 Less than Twelve Months Twelve Months or Longer Total Description of Securities Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Fixed maturities available for sale: Investment grade securities: U.S. Government direct, guaranteed, and government-sponsored enterprises $ 34,388 $ (422 ) $ 47,514 $ (951 ) $ 81,902 $ (1,373 ) States, municipalities and political subdivisions 4,561 (21 ) 1,771 (9 ) 6,332 (30 ) Corporates, by sector: Financial 133,080 (652 ) 35,302 (1,429 ) 168,382 (2,081 ) Utilities 48,562 (569 ) 32,345 (729 ) 80,907 (1,298 ) Energy 23,463 (81 ) 67,775 (3,682 ) 91,238 (3,763 ) Other corporate sectors 220,661 (2,312 ) 163,886 (4,257 ) 384,547 (6,569 ) Total corporates 425,766 (3,614 ) 299,308 (10,097 ) 725,074 (13,711 ) Redeemable preferred stocks, by sector: Utilities — — 5,953 (97 ) 5,953 (97 ) Total redeemable preferred stocks — — 5,953 (97 ) 5,953 (97 ) Total investment grade securities 464,715 (4,057 ) 354,546 (11,154 ) 819,261 (15,211 ) Below investment grade securities: States, municipalities and political subdivisions 200 (105 ) — — 200 (105 ) Corporates, by sector: Financial — — 84,432 (21,311 ) 84,432 (21,311 ) Energy 8,114 (104 ) 75,204 (21,525 ) 83,318 (21,629 ) Other corporate sectors 25,334 (5,066 ) 54,383 (8,981 ) 79,717 (14,047 ) Total corporates 33,448 (5,170 ) 214,019 (51,817 ) 247,467 (56,987 ) Collateralized debt obligations — — 12,347 (7,653 ) 12,347 (7,653 ) Redeemable preferred stocks, by sector: Financial — — 24,376 (2,727 ) 24,376 (2,727 ) Total redeemable preferred stocks — — 24,376 (2,727 ) 24,376 (2,727 ) Total below investment grade securities 33,648 (5,275 ) 250,742 (62,197 ) 284,390 (67,472 ) Total fixed maturities $ 498,363 $ (9,332 ) $ 605,288 $ (73,351 ) $ 1,103,651 $ (82,683 )

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Summary of Effective Income Tax Rate	The effective income tax rate differed from the expected rate for the three and six month periods ended June 30, 2018 and 2017 as shown below: Three Months Ended June 30, 2018 % 2017 % Expected income taxes $ 47,641 21.0 $ 70,674 35.0 Increase (reduction) in income taxes resulting from: Low income housing investments (3,324 ) (1.5 ) (4,649 ) (2.3 ) Share-based awards (2,055 ) (0.9 ) (4,018 ) (2.0 ) Other 209 0.1 (444 ) (0.2 ) Income tax expense (benefit) from continuing operations $ 42,471 18.7 $ 61,563 30.5 Six Months Ended June 30, 2018 % 2017 % Expected income taxes $ 92,338 21.0 $ 137,783 35.0 Increase (reduction) in income taxes resulting from: Low income housing investments (6,649 ) (1.5 ) (9,298 ) (2.4 ) Share-based awards (4,254 ) (1.0 ) (9,439 ) (2.4 ) Other 167 — (2,920 ) (0.7 ) Income tax expense (benefit) from continuing operations $ 81,602 18.5 $ 116,126 29.5

Liability for Unpaid Claims (Ta

Liability for Unpaid Claims (Tables)	6 Months Ended
	Jun. 30, 2018
Insurance [Abstract]
Activity in the Liability for Unpaid Health Claims	Activity in the liability for unpaid health claims is summarized as follows: Six Months Ended 2018 2017 Balance at beginning of period $ 146,865 $ 143,128 Incurred related to: Current year 269,574 264,648 Prior years (5,708 ) (8,364 ) Total incurred 263,866 256,284 Paid related to: Current year 171,199 164,271 Prior years 99,054 94,676 Total paid 270,253 258,947 Balance at end of period $ 140,478 $ 140,465
Reconciliation of the Liability for Policy Claims and Other Benefits Payable	Below is the reconciliation of the liability for "Policy claims and other benefits payable" in the Condensed Consolidated Balance Sheets . June 30, December 31, 2017 Policy claims and other benefits payable: Life insurance $ 188,991 $ 186,429 Health insurance 140,478 146,865 Total $ 329,469 $ 333,294

Postretirement Benefits (Tables

Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
Summary of Post-Retirement Benefit Costs by Component	The following tables present a summary of post-retirement benefit costs by component for the three and six month periods ended June 30, 2018 and 2017 . Components of Post-Retirement Benefit Costs Three Months Ended June 30, Pension Benefits Other Benefits 2018 2017 2018 2017 Service cost $ 5,277 $ 4,484 $ — $ — Interest cost 5,493 5,551 228 250 Expected return on assets (6,363 ) (5,898 ) — — Amortization: Prior service cost 119 119 — — Actuarial (gain) loss 3,636 2,952 23 38 Direct recognition of expense — — 85 116 Net periodic benefit cost $ 8,162 $ 7,208 $ 336 $ 404 Six Months Ended June 30, Pension Benefits Other Benefits 2018 2017 2018 2017 Service cost $ 10,554 $ 8,971 $ — $ — Interest cost 10,986 11,101 456 500 Expected return on assets (12,726 ) (11,797 ) — — Amortization: Prior service cost 238 238 — — Actuarial (gain)/loss 7,272 5,903 46 77 Direct recognition of expense — — 225 212 Net periodic benefit cost $ 16,324 $ 14,416 $ 727 $ 789
Schedule of Assets at Fair Value for Defined-Benefit Pension Plans	The following tables present the assets of Torchmark’s defined benefit pension plans at June 30, 2018 and December 31, 2017 . Pension Assets by Component at June 30, 2018 Fair Value Determined by: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Amount % to Total Corporate bonds: Financial $ $ 46,501 $ $ 46,501 12 Utilities 40,032 40,032 10 Energy 23,551 23,551 6 Other corporates 67,960 67,960 17 Total corporate bonds — 178,044 — 178,044 45 Exchange traded fund (1) 168,743 168,743 43 Other bonds 245 245 — Other long-term investments 3,998 3,998 1 Guaranteed annuity contract (2) 21,427 21,427 5 Short-term investments 18,660 18,660 5 Other 1,866 1,866 1 Grand Total $ 189,269 $ 203,714 $ — $ 392,983 100 (1) A fund including marketable securities that mirror the S&P 500 index. (2) Representing a guaranteed annuity contract issued by Torchmark's subsidiary, American Income Life Insurance Company, to fund the obligations of the American Income Pension Plan. Pension Assets by Component at December 31, 2017 Fair Value Determined by: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Amount % to Total Corporate bonds: Financial $ $ 43,451 $ $ 43,451 12 Utilities 46,144 46,144 12 Energy 25,023 25,023 7 Other corporates 65,888 65,888 17 Total corporate bonds — 180,506 — 180,506 48 Exchange traded fund (1) 164,351 164,351 43 Other bonds 256 256 — Other long-term investments 2,304 2,304 1 Guaranteed annuity contract (2) 21,202 21,202 6 Short-term investments 3,984 3,984 1 Other 5,021 5,021 1 Grand Total $ 173,356 $ 204,268 $ — $ 377,624 100 (1) A fund including marketable securities that mirror the S&P 500 index. (2) Representing a guaranteed annuity contract issued by Torchmark's subsidiary, American Income Life Insurance Company, to fund the obligations of the American Income Pension Plan.
Pension Liability	The following table presents liabilities for the defined-benefit pension plans at June 30, 2018 and December 31, 2017 . Pension Liability June 30, December 31, 2017 Funded defined benefit pension $ 509,965 $ 518,141 SERPs (1) 85,382 84,465 Pension Benefit Obligation $ 595,347 $ 602,606 (1) Supplemental executive retirement plan (SERP).
Schedule of Defined Benefit Plans Disclosures	The following table includes information regarding the SERPs at June 30, 2018 and December 31, 2017 . June 30, December 31, 2017 Premiums paid for insurance coverage $ 1,047 $ 2,050 Total investments: Company owned life insurance $ 41,872 $ 40,273 Exchange traded funds 55,051 55,442 $ 96,923 $ 95,715 Liability: Active plan $ 82,862 $ 81,457 Closed plan 2,520 3,008 $ 85,382 $ 84,465

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Weighted-Average Shares Outstanding	A reconciliation of basic and diluted weighted-average shares outstanding is as follows: Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Basic weighted average shares outstanding 113,350,175 116,646,669 113,762,340 117,205,467 Weighted average dilutive options outstanding 2,301,237 2,449,882 2,434,633 2,554,158 Diluted weighted average shares outstanding 115,651,412 119,096,551 116,196,973 119,759,625 Antidilutive shares 1,381,686 1,444,280 960,753 1,037,328

Business Segments (Tables)

Business Segments (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Reconciliation of Segment Operating Information to Consolidated Statement of Operations	The following tables set forth a reconciliation of Torchmark’s revenues and operations by segment to its pre-tax income and each significant line item in its Condensed Consolidated Statements of Operations . Reconciliation of Segment Operating Information to the Condensed Consolidated Statement of Operations Three Months Ended June 30, 2018 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 602,534 $ 251,440 $ 5 $ 853,979 Net investment income $ 218,568 218,568 Other income $ 441 $ (25 ) (2) 416 Total revenue 602,534 251,440 5 218,568 441 (25 ) 1,072,963 Expenses: Policy benefits 399,334 160,461 8,582 568,377 Required interest on reserves (158,101 ) (20,726 ) (11,885 ) 190,712 — Required interest on DAC 48,275 6,079 150 (54,504 ) — Amortization of acquisition costs 104,599 23,892 586 129,077 Commissions, premium taxes, and non-deferred acquisition costs 47,250 22,196 6 (25 ) (2) 69,427 Insurance administrative expense (1) 55,276 55,276 Parent expense 2,847 2,847 Stock-based compensation expense 10,497 10,497 Interest expense 22,411 22,411 Total expenses 441,357 191,902 (2,561 ) 158,619 68,620 (25 ) 857,912 Subtotal 161,177 59,538 2,566 59,949 (68,179 ) — 215,051 Non-operating items — — Measure of segment profitability (pretax) $ 161,177 $ 59,538 $ 2,566 $ 59,949 $ (68,179 ) $ — 215,051 Deduct applicable income taxes (39,991 ) Net operating income 175,060 Add back income taxes applicable to segment profitability 39,991 Add (deduct) realized investment gains (losses) 11,813 Income before income taxes per Condensed Consolidated Statement of Operations $ 226,864 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. Three Months Ended June 30, 2017 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 573,836 $ 242,775 $ 3 $ 816,614 Net investment income $ 212,776 212,776 Other income $ 427 $ (34 ) (2) 393 Total revenue 573,836 242,775 3 212,776 427 (34 ) 1,029,783 Expenses: Policy benefits 388,765 156,579 8,977 2,094 (3) 556,415 Required interest on reserves (150,652 ) (19,267 ) (12,394 ) 182,313 — Required interest on DAC 46,213 5,840 174 (52,227 ) — Amortization of acquisition costs 98,473 23,016 632 122,121 Commissions, premium taxes, and non-deferred acquisition costs 43,708 21,351 7 (34 ) (2) 65,032 Insurance administrative expense (1) 51,412 51,412 Parent expense 2,665 2,665 Stock-based compensation expense 8,351 8,351 Interest expense 21,156 21,156 Total expenses 426,507 187,519 (2,604 ) 151,242 62,428 2,060 827,152 Subtotal 147,329 55,256 2,607 61,534 (62,001 ) (2,094 ) 202,631 Non-operating items 2,094 (3) 2,094 Measure of segment profitability (pretax) $ 147,329 $ 55,256 $ 2,607 $ 61,534 $ (62,001 ) $ — 204,725 Deduct applicable income taxes (62,543 ) Net operating income 142,182 Add back income taxes applicable to segment profitability 62,543 Add (deduct) realized investment gains (losses) (705 ) Add (deduct) administrative settlements (3) (2,094 ) Income before income taxes per Condensed Consolidated Statement of Operations $ 201,926 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. (3) Administrative settlements. Six Months Ended June 30, 2018 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 1,200,837 $ 503,238 $ 10 $ 1,704,085 Net investment income $ 436,652 436,652 Other income $ 764 $ (53 ) (2) 711 Total revenue 1,200,837 503,238 10 436,652 764 (53 ) 2,141,448 Expenses: Policy benefits 799,915 321,080 17,271 1,138,266 Required interest on reserves (314,315 ) (41,130 ) (23,902 ) 379,347 — Required interest on DAC 96,219 12,092 303 (108,614 ) — Amortization of acquisition costs 208,376 49,149 1,172 258,697 Commissions, premium taxes, and non-deferred acquisition costs 94,644 44,461 14 (53 ) (2) 139,066 Insurance administrative expense (1) 110,748 110,748 Parent expense 5,139 5,139 Stock-based compensation expense 19,557 19,557 Interest expense 44,033 44,033 Total expenses 884,839 385,652 (5,142 ) 314,766 135,444 (53 ) 1,715,506 Subtotal 315,998 117,586 5,152 121,886 (134,680 ) — 425,942 Non-operating items — — Measure of segment profitability (pretax) $ 315,998 $ 117,586 $ 5,152 $ 121,886 $ (134,680 ) $ — 425,942 Deduct applicable income taxes (78,712 ) Net operating income 347,230 Add back income taxes applicable to segment profitability 78,712 Add (deduct) realized investment gains (losses) 13,764 Income before income taxes per Condensed Consolidated Statements of Operations $ 439,706 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. Six Months Ended June 30, 2017 Life Health Annuity Investment Corporate & Other Adjustments Consolidated Revenue: Premium $ 1,149,673 $ 487,566 $ 6 $ 1,637,245 Net investment income $ 421,058 421,058 Other income $ 878 $ (69 ) (2) 809 Total revenue 1,149,673 487,566 6 421,058 878 (69 ) 2,059,112 Expenses: Policy benefits 779,844 314,330 17,923 2,094 (3) 1,114,191 Required interest on reserves (299,477 ) (38,242 ) (24,812 ) 362,531 — Required interest on DAC 92,149 11,649 352 (104,150 ) — Amortization of acquisition costs 198,378 48,343 1,308 248,029 Commissions, premium taxes, and non-deferred acquisition costs 87,346 42,853 18 (69 ) (2) 130,148 Insurance administrative expense (1) 103,325 103,325 Parent expense 4,898 4,898 Stock-based compensation expense 16,546 16,546 Interest expense 41,855 41,855 Total expenses 858,240 378,933 (5,211 ) 300,236 124,769 2,025 1,658,992 Subtotal 291,433 108,633 5,217 120,822 (123,891 ) (2,094 ) 400,120 Non-operating items 2,094 (3) 2,094 Measure of segment profitability (pretax) $ 291,433 $ 108,633 $ 5,217 $ 120,822 $ (123,891 ) $ — 402,214 Deduct applicable income taxes (121,361 ) Net operating income 280,853 Add back income taxes applicable to segment profitability 121,361 Add (deduct) realized investment gains (losses) (6,453 ) Add (deduct) administrative settlements (3) (2,094 ) Income before income taxes per Condensed Consolidated Statements of Operations $ 393,667 (1) Administrative expense is not allocated to insurance segments. (2) Elimination of intersegment commission. (3) Administrative settlements.

New Accounting Standards (Detai

New Accounting Standards (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings	$ 5,115,071		$ 4,806,208
Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings				$ 4,900
Accounting Standards Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net periodic benefit costs	1,600
Accounting Standards Update 2018-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI to retained earnings			252,000
Scenario, Forecast [Member] | Accounting Standards Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net periodic benefit costs		$ 3,500
Fair Value Option [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investments, fair value disclosure	108,452
Partnership Interest [Member] | Fair Value Option [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investments, fair value disclosure	$ 108,452		$ 0

Supplemental Information abou28

Supplemental Information about Changes to Accumulated Other Comprehensive Income - Schedule of Analysis of Change in Balance by Component of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance			$ 6,231,421	$ 4,566,861
Other comprehensive income (loss) before reclassifications, net of tax	$ (332,921)	$ 259,271	(819,431)	403,498
Reclassifications, net of tax	(3,779)	2,424	(1,344)	3,488
Other comprehensive income (loss)	(336,700)	261,695	(820,775)	406,986
Stockholders' equity, ending balance	5,571,609	5,053,416	5,571,609	5,053,416
Available for Sale Assets [Member]
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance	1,082,896	832,057	1,569,289	692,314
Other comprehensive income (loss) before reclassifications, net of tax	(329,619)	257,595	(815,462)	398,295
Reclassifications, net of tax	(6,763)	403	(7,313)	(554)
Other comprehensive income (loss)	(336,382)	257,998	(822,775)	397,741
Stockholders' equity, ending balance	746,514	1,090,055	746,514	1,090,055
Deferred Acquisition Costs [Member]
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance	(8,191)	(7,182)	(8,547)	(6,682)
Other comprehensive income (loss) before reclassifications, net of tax	1,612	(473)	1,968	(973)
Reclassifications, net of tax	0	0	0	0
Other comprehensive income (loss)	1,612	(473)	1,968	(973)
Stockholders' equity, ending balance	(6,579)	(7,655)	(6,579)	(7,655)
Foreign Exchange [Member]
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance	15,279	8,753	16,302	4,967
Other comprehensive income (loss) before reclassifications, net of tax	(4,914)	2,149	(5,937)	5,935
Reclassifications, net of tax	0	0	0	0
Other comprehensive income (loss)	(4,914)	2,149	(5,937)	5,935
Stockholders' equity, ending balance	10,365	10,902	10,365	10,902
Pension Adjustments [Member]
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance	(149,785)	(110,763)	(152,770)	(113,025)
Other comprehensive income (loss) before reclassifications, net of tax	0	0	0	241
Reclassifications, net of tax	2,984	2,021	5,969	4,042
Other comprehensive income (loss)	2,984	2,021	5,969	4,283
Stockholders' equity, ending balance	(146,801)	(108,742)	(146,801)	(108,742)
Total [Member]
Accumulated Other Comprehensive Income, Net of Tax [Roll Forward]
Stockholders' equity, beginning balance	940,199	722,865	1,424,274	577,574
Stockholders' equity, ending balance	$ 603,499	$ 984,560	$ 603,499	$ 984,560

Supplemental Information abou29

Supplemental Information about Changes to Accumulated Other Comprehensive Income - Summary of Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Unrealized investment gains (losses) on available for sale assets:
Realized (gains) losses	$ (11,813)	$ 705	$ (13,764)	$ 6,453
Amortization of (discount) premium	(218,568)	(212,776)	(436,652)	(421,058)
Total before tax	(226,864)	(201,926)	(439,706)	(393,667)
Tax	42,471	61,563	81,602	116,126
Net income	(184,425)	(140,273)	(358,025)	(273,814)
Pension adjustments:
Total reclassifications (after tax)	(3,779)	2,424	(1,344)	3,488
Unrealized Investment Gains (Losses) on Available for Sale Assets [Member]
Pension adjustments:
Total reclassifications (after tax)	(6,763)	403	(7,313)	(554)
Pension Adjustments [Member]
Pension adjustments:
Total reclassifications (after tax)	2,984	2,021	5,969	4,042
Reclassification out of Accumulated Other Comprehensive Income [Member]
Pension adjustments:
Total reclassifications (after tax)	(3,779)	2,424	(1,344)	3,488
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Investment Gains (Losses) on Available for Sale Assets [Member]
Unrealized investment gains (losses) on available for sale assets:
Realized (gains) losses	(9,431)	681	(10,817)	(354)
Amortization of (discount) premium	870	(61)	1,560	(498)
Total before tax	(8,561)	620	(9,257)	(852)
Tax	1,798	(217)	1,944	298
Net income	(6,763)	403	(7,313)	(554)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Amortization of Prior Service Cost [Member]
Pension adjustments:
Pension adjustments	119	119	238	238
Reclassification out of Accumulated Other Comprehensive Income [Member] | Amortization of Actuarial Gain (Loss) [Member]
Pension adjustments:
Pension adjustments	3,659	2,990	7,318	5,980
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension Adjustments [Member]
Pension adjustments:
Pension adjustments reclassified out of accumulated other comprehensive income	3,778	3,109	7,556	6,218
Tax	(794)	(1,088)	(1,587)	(2,176)
Total reclassifications (after tax)	$ 2,984	$ 2,021	$ 5,969	$ 4,042

Investments - Summary of Fixed

Investments - Summary of Fixed Maturities Available for Sale by Component (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 15,350,152	$ 14,995,101
Fair Value	16,284,691	16,969,325
Fixed maturities available for sale [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	15,350,152	14,995,101
Gross Unrealized Gains	1,200,602	2,056,907
Gross Unrealized Losses	(266,063)	(82,683)
Fair Value	$ 16,284,691	$ 16,969,325
Percentage of Total Fixed Maturities	100.00%	100.00%
Fixed maturities available for sale [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 390,021	$ 390,646
Gross Unrealized Gains	2,266	18,173
Gross Unrealized Losses	(4,383)	(1,373)
Fair Value	$ 387,904	$ 407,446
Percentage of Total Fixed Maturities	2.00%	2.00%
Fixed maturities available for sale [Member] | States, municipalities, and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 1,232,142	$ 1,091,960
Gross Unrealized Gains	103,365	127,890
Gross Unrealized Losses	(281)	(135)
Fair Value	$ 1,335,226	$ 1,219,715
Percentage of Total Fixed Maturities	9.00%	7.00%
Fixed maturities available for sale [Member] | Foreign governments [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 19,609	$ 20,236
Gross Unrealized Gains	1,705	1,782
Gross Unrealized Losses	0	0
Fair Value	$ 21,314	$ 22,018
Percentage of Total Fixed Maturities	0.00%	0.00%
Fixed maturities available for sale [Member] | Corporates [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 13,123,413	$ 12,923,415
Gross Unrealized Gains	1,020,602	1,819,119
Gross Unrealized Losses	(250,273)	(70,698)
Fair Value	$ 13,893,742	$ 14,671,836
Percentage of Total Fixed Maturities	86.00%	87.00%
Fixed maturities available for sale [Member] | Corporates [Member] | Financial [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 3,372,221	$ 3,282,526
Gross Unrealized Gains	269,494	475,961
Gross Unrealized Losses	(51,445)	(23,392)
Fair Value	$ 3,590,270	$ 3,735,095
Percentage of Total Fixed Maturities	22.00%	22.00%
Fixed maturities available for sale [Member] | Corporates [Member] | Utilities [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 1,947,899	$ 1,955,737
Gross Unrealized Gains	255,504	369,406
Gross Unrealized Losses	(12,164)	(1,298)
Fair Value	$ 2,191,239	$ 2,323,845
Percentage of Total Fixed Maturities	14.00%	14.00%
Fixed maturities available for sale [Member] | Corporates [Member] | Energy [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 1,619,674	$ 1,619,349
Gross Unrealized Gains	133,584	226,140
Gross Unrealized Losses	(40,101)	(25,392)
Fair Value	$ 1,713,157	$ 1,820,097
Percentage of Total Fixed Maturities	11.00%	11.00%
Fixed maturities available for sale [Member] | Corporates [Member] | Other corporate sectors [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 6,183,619	$ 6,065,803
Gross Unrealized Gains	362,020	747,612
Gross Unrealized Losses	(146,563)	(20,616)
Fair Value	$ 6,399,076	$ 6,792,799
Percentage of Total Fixed Maturities	39.00%	40.00%
Fixed maturities available for sale [Member] | Collateralized debt obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 58,582	$ 59,150
Gross Unrealized Gains	23,437	20,084
Gross Unrealized Losses	(5,823)	(7,653)
Fair Value	$ 76,196	$ 71,581
Percentage of Total Fixed Maturities	0.00%	0.00%
Fixed maturities available for sale [Member] | Other asset-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 150,843	$ 144,520
Gross Unrealized Gains	2,386	4,835
Gross Unrealized Losses	(429)	0
Fair Value	$ 152,800	$ 149,355
Percentage of Total Fixed Maturities	1.00%	1.00%
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 375,542	$ 365,174
Gross Unrealized Gains	46,841	65,024
Gross Unrealized Losses	(4,874)	(2,824)
Fair Value	$ 417,509	$ 427,374
Percentage of Total Fixed Maturities	2.00%	3.00%
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 347,014	$ 336,621
Gross Unrealized Gains	45,481	62,892
Gross Unrealized Losses	(4,518)	(2,727)
Fair Value	$ 387,977	$ 396,786
Percentage of Total Fixed Maturities	2.00%	3.00%
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 28,528	$ 28,553
Gross Unrealized Gains	1,360	2,132
Gross Unrealized Losses	(356)	(97)
Fair Value	$ 29,532	$ 30,588
Percentage of Total Fixed Maturities	0.00%	0.00%

Investments - Schedule of Fixed

Investments - Schedule of Fixed Maturities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Amortized Cost
Due in one year or less	$ 80,564
Due after one year through five years	732,395
Due after five years through ten years	1,611,476
Due after ten years through twenty years	5,051,297
Due after twenty years	7,664,183
Mortgage-backed and asset-backed securities	210,237
Cost or Amortized Cost	15,350,152	$ 14,995,101
Fair Value
Due in one year or less	81,901
Due after one year through five years	757,040
Due after five years through ten years	1,745,491
Due after ten years through twenty years	5,607,509
Due after twenty years	7,862,890
Mortgage-backed and asset-backed securities	229,860
Fair Value	$ 16,284,691	$ 16,969,325

Investments - Assets Measured a

Investments - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 16,284,691	$ 16,969,325
Percent of total	100.00%	100.00%
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of total	0.00%	0.00%
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of total	95.90%	96.10%
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of total	4.10%	3.90%
Fixed maturities available for sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 16,284,691	$ 16,969,325
Fixed maturities available for sale [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	387,904	407,446
Fixed maturities available for sale [Member] | States, municipalities, and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,335,226	1,219,715
Fixed maturities available for sale [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	21,314	22,018
Fixed maturities available for sale [Member] | Corporates [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	13,893,742	14,671,836
Fixed maturities available for sale [Member] | Corporates [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,590,270	3,735,095
Fixed maturities available for sale [Member] | Corporates [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,191,239	2,323,845
Fixed maturities available for sale [Member] | Corporates [Member] | Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,713,157	1,820,097
Fixed maturities available for sale [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	6,399,076	6,792,799
Fixed maturities available for sale [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	76,196	71,581
Fixed maturities available for sale [Member] | Other asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	152,800	149,355
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	417,509	427,374
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	387,977	396,786
Fixed maturities available for sale [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	29,532	30,588
Fixed maturities available for sale [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	44
Fixed maturities available for sale [Member] | Level 1 [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | States, municipalities, and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	44
Fixed maturities available for sale [Member] | Level 1 [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Corporates [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Corporates [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Corporates [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Corporates [Member] | Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Other asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Redeemable preferred stocks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 1 [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	15,618,532	16,300,841
Fixed maturities available for sale [Member] | Level 2 [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	387,904	407,446
Fixed maturities available for sale [Member] | Level 2 [Member] | States, municipalities, and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,335,226	1,219,671
Fixed maturities available for sale [Member] | Level 2 [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	21,314	22,018
Fixed maturities available for sale [Member] | Level 2 [Member] | Corporates [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	13,316,932	14,089,026
Fixed maturities available for sale [Member] | Level 2 [Member] | Corporates [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,529,651	3,673,089
Fixed maturities available for sale [Member] | Level 2 [Member] | Corporates [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,044,141	2,168,115
Fixed maturities available for sale [Member] | Level 2 [Member] | Corporates [Member] | Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,673,305	1,779,281
Fixed maturities available for sale [Member] | Level 2 [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	6,069,835	6,468,541
Fixed maturities available for sale [Member] | Level 2 [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 2 [Member] | Other asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	139,647	135,306
Fixed maturities available for sale [Member] | Level 2 [Member] | Redeemable preferred stocks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	417,509	427,374
Fixed maturities available for sale [Member] | Level 2 [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	387,977	396,786
Fixed maturities available for sale [Member] | Level 2 [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	29,532	30,588
Fixed maturities available for sale [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	666,159	668,440
Fixed maturities available for sale [Member] | Level 3 [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 3 [Member] | States, municipalities, and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 3 [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 3 [Member] | Corporates [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	576,810	582,810
Fixed maturities available for sale [Member] | Level 3 [Member] | Corporates [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	60,619	62,006
Fixed maturities available for sale [Member] | Level 3 [Member] | Corporates [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	147,098	155,730
Fixed maturities available for sale [Member] | Level 3 [Member] | Corporates [Member] | Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	39,852	40,816
Fixed maturities available for sale [Member] | Level 3 [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	329,241	324,258
Fixed maturities available for sale [Member] | Level 3 [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	76,196	71,581
Fixed maturities available for sale [Member] | Level 3 [Member] | Other asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	13,153	14,049
Fixed maturities available for sale [Member] | Level 3 [Member] | Redeemable preferred stocks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 3 [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed maturities available for sale [Member] | Level 3 [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0

Investments - Schedule of Chang

Investments - Schedule of Changes in Assets Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 668,440	$ 623,103
Total gains or losses:
Included in realized gains/losses	0	0
Included in other comprehensive income	(15,125)	15,495
Acquisitions	20,300	35,666
Sales	0	0
Amortization	2,397	2,489
Other	(9,853)	(10,069)
Transfers in and/or out of Level 3	0	0
Ending balance	$ 666,159	$ 666,684
Percent of total fixed maturities	4.10%	4.10%
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 14,049	$ 0
Total gains or losses:
Included in realized gains/losses	0	0
Included in other comprehensive income	(697)	261
Acquisitions	0	14,000
Sales	0	0
Amortization	0	0
Other	(199)	(108)
Transfers in and/or out of Level 3	0	0
Ending balance	$ 13,153	$ 14,153
Percent of total fixed maturities	0.10%	0.10%
Collateralized debt obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 71,581	$ 63,503
Total gains or losses:
Included in realized gains/losses	0	0
Included in other comprehensive income	5,183	3,597
Acquisitions	0	0
Sales	0	0
Amortization	2,389	2,481
Other	(2,957)	(3,336)
Transfers in and/or out of Level 3	0	0
Ending balance	$ 76,196	$ 66,245
Percent of total fixed maturities	0.50%	0.40%
Corporates [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 582,810	$ 559,600
Total gains or losses:
Included in realized gains/losses	0	0
Included in other comprehensive income	(19,611)	11,637
Acquisitions	20,300	21,666
Sales	0	0
Amortization	8	8
Other	(6,697)	(6,625)
Transfers in and/or out of Level 3	0	0
Ending balance	$ 576,810	$ 586,286
Percent of total fixed maturities	3.50%	3.60%

Investments - Additional Inform

Investments - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2018USD ($)Issue	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)Issue	Jun. 30, 2017USD ($)	Dec. 31, 2017Issue
Gain (Loss) on Securities [Line Items]
Total issues of fixed maturity portfolio | Issue	1,532		1,532		1,502
Fixed Maturities [Member]
Gain (Loss) on Securities [Line Items]
Other than-temporary impairment, available for sale securities	$ 0	$ 245,000	$ 0	$ 245,000
Other-than-temporary impairment, available for sale securities, net of tax		$ 159,000		$ 159,000

Investments - Transfers in and

Investments - Transfers in and Out of Each of the Valuation Levels of Fair Values (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Level 1 [Member]
Transfers In And Out Of Each Of Valuation Levels Of Fair Values Of Investments [Line Items]
In		$ 4
Out	0	(597)
Net	0	(593)
Level 2 [Member]
Transfers In And Out Of Each Of Valuation Levels Of Fair Values Of Investments [Line Items]
In	0	597
Out	0	(4)
Net	0	593
Level 3 [Member]
Transfers In And Out Of Each Of Valuation Levels Of Fair Values Of Investments [Line Items]
In	0	0
Out	0	0
Net	$ 0	$ 0

Investments - Fair Value Option

Investments - Fair Value Option (Details) - Fair Value Option [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items] (Deprecated 2018-01-31)
Investments, fair value disclosure	$ 108,452
Net Gains and Losses Recognized During the Period	2,861
Less Net Gains and Losses Recognized due to Sales	0
Total Changes in Fair Values Included in Current-Period Earnings	2,861
Level 1 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items] (Deprecated 2018-01-31)
Investments, fair value disclosure	0
Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items] (Deprecated 2018-01-31)
Investments, fair value disclosure	108,452
Level 3 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items] (Deprecated 2018-01-31)
Investments, fair value disclosure	$ 0

Investments - Schedule of Infor

Investments - Schedule of Information about Investments in Unrealized Loss Position (Details) - Issue	Jun. 30, 2018	Dec. 31, 2017
Number of issues (Cusip numbers) held:
Less than Twelve Months	489	92
Twelve Months or Longer	99	102
Total	588	194

Investments - Schedule of Unrea

Investments - Schedule of Unrealized Investment Losses by Class of Investment (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value
Fair Value, Less than Twelve Months	$ 4,193,673	$ 498,363
Fair Value, Twelve Months or Longer	553,770	605,288
Fair Value, Total	4,747,443	1,103,651
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(176,892)	(9,332)
Unrealized Loss, Twelve Months or Longer	(89,171)	(73,351)
Unrealized Loss, Total	(266,063)	(82,683)
Investment grade [Member]
Fair Value
Fair Value, Less than Twelve Months	4,047,618	464,715
Fair Value, Twelve Months or Longer	334,461	354,546
Fair Value, Total	4,382,079	819,261
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(163,985)	(4,057)
Unrealized Loss, Twelve Months or Longer	(33,551)	(11,154)
Unrealized Loss, Total	(197,536)	(15,211)
Investment grade [Member] | U.S. Government direct, guaranteed, and government-sponsored enterprises [Member]
Fair Value
Fair Value, Less than Twelve Months	172,110	34,388
Fair Value, Twelve Months or Longer	38,389	47,514
Fair Value, Total	210,499	81,902
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(3,061)	(422)
Unrealized Loss, Twelve Months or Longer	(1,322)	(951)
Unrealized Loss, Total	(4,383)	(1,373)
Investment grade [Member] | States, municipalities, and political subdivisions [Member]
Fair Value
Fair Value, Less than Twelve Months	35,311	4,561
Fair Value, Twelve Months or Longer	1,190	1,771
Fair Value, Total	36,501	6,332
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(268)	(21)
Unrealized Loss, Twelve Months or Longer	(13)	(9)
Unrealized Loss, Total	(281)	(30)
Investment grade [Member] | Corporates [Member]
Fair Value
Fair Value, Less than Twelve Months	3,793,150	425,766
Fair Value, Twelve Months or Longer	289,215	299,308
Fair Value, Total	4,082,365	725,074
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(159,547)	(3,614)
Unrealized Loss, Twelve Months or Longer	(31,860)	(10,097)
Unrealized Loss, Total	(191,407)	(13,711)
Investment grade [Member] | Corporates [Member] | Financial [Member]
Fair Value
Fair Value, Less than Twelve Months	816,233	133,080
Fair Value, Twelve Months or Longer	53,487	35,302
Fair Value, Total	869,720	168,382
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(29,495)	(652)
Unrealized Loss, Twelve Months or Longer	(3,995)	(1,429)
Unrealized Loss, Total	(33,490)	(2,081)
Investment grade [Member] | Corporates [Member] | Utilities [Member]
Fair Value
Fair Value, Less than Twelve Months	292,562	48,562
Fair Value, Twelve Months or Longer	31,417	32,345
Fair Value, Total	323,979	80,907
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(10,578)	(569)
Unrealized Loss, Twelve Months or Longer	(1,501)	(729)
Unrealized Loss, Total	(12,079)	(1,298)
Investment grade [Member] | Corporates [Member] | Energy [Member]
Fair Value
Fair Value, Less than Twelve Months	221,851	23,463
Fair Value, Twelve Months or Longer	49,555	67,775
Fair Value, Total	271,406	91,238
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(10,100)	(81)
Unrealized Loss, Twelve Months or Longer	(7,078)	(3,682)
Unrealized Loss, Total	(17,178)	(3,763)
Investment grade [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value
Fair Value, Less than Twelve Months	2,462,504	220,661
Fair Value, Twelve Months or Longer	154,756	163,886
Fair Value, Total	2,617,260	384,547
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(109,374)	(2,312)
Unrealized Loss, Twelve Months or Longer	(19,286)	(4,257)
Unrealized Loss, Total	(128,660)	(6,569)
Investment grade [Member] | Other asset-backed securities [Member]
Fair Value
Fair Value, Less than Twelve Months	36,920
Fair Value, Twelve Months or Longer	0
Fair Value, Total	36,920
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(429)
Unrealized Loss, Twelve Months or Longer	0
Unrealized Loss, Total	(429)
Investment grade [Member] | Redeemable preferred stocks [Member]
Fair Value
Fair Value, Less than Twelve Months	10,127	0
Fair Value, Twelve Months or Longer	5,667	5,953
Fair Value, Total	15,794	5,953
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(680)	0
Unrealized Loss, Twelve Months or Longer	(356)	(97)
Unrealized Loss, Total	(1,036)	(97)
Investment grade [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value
Fair Value, Less than Twelve Months	10,127
Fair Value, Twelve Months or Longer	0
Fair Value, Total	10,127
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(680)
Unrealized Loss, Twelve Months or Longer	0
Unrealized Loss, Total	(680)
Investment grade [Member] | Redeemable preferred stocks [Member] | Utilities [Member]
Fair Value
Fair Value, Less than Twelve Months	0	0
Fair Value, Twelve Months or Longer	5,667	5,953
Fair Value, Total	5,667	5,953
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	0	0
Unrealized Loss, Twelve Months or Longer	(356)	(97)
Unrealized Loss, Total	(356)	(97)
Below investment grade [Member]
Fair Value
Fair Value, Less than Twelve Months	146,055	33,648
Fair Value, Twelve Months or Longer	219,309	250,742
Fair Value, Total	365,364	284,390
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(12,907)	(5,275)
Unrealized Loss, Twelve Months or Longer	(55,620)	(62,197)
Unrealized Loss, Total	(68,527)	(67,472)
Below investment grade [Member] | States, municipalities, and political subdivisions [Member]
Fair Value
Fair Value, Less than Twelve Months		200
Fair Value, Twelve Months or Longer		0
Fair Value, Total		200
Unrealized Loss
Unrealized Loss, Less Than Twelve Months		(105)
Unrealized Loss, Twelve Months or Longer		0
Unrealized Loss, Total		(105)
Below investment grade [Member] | Corporates [Member]
Fair Value
Fair Value, Less than Twelve Months	146,055	33,448
Fair Value, Twelve Months or Longer	181,880	214,019
Fair Value, Total	327,935	247,467
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(12,907)	(5,170)
Unrealized Loss, Twelve Months or Longer	(45,959)	(51,817)
Unrealized Loss, Total	(58,866)	(56,987)
Below investment grade [Member] | Corporates [Member] | Financial [Member]
Fair Value
Fair Value, Less than Twelve Months	26,070	0
Fair Value, Twelve Months or Longer	61,706	84,432
Fair Value, Total	87,776	84,432
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(4,704)	0
Unrealized Loss, Twelve Months or Longer	(13,251)	(21,311)
Unrealized Loss, Total	(17,955)	(21,311)
Below investment grade [Member] | Corporates [Member] | Utilities [Member]
Fair Value
Fair Value, Less than Twelve Months	15,098
Fair Value, Twelve Months or Longer	0
Fair Value, Total	15,098
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(85)
Unrealized Loss, Twelve Months or Longer	0
Unrealized Loss, Total	(85)
Below investment grade [Member] | Corporates [Member] | Energy [Member]
Fair Value
Fair Value, Less than Twelve Months	26,166	8,114
Fair Value, Twelve Months or Longer	67,777	75,204
Fair Value, Total	93,943	83,318
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(1,010)	(104)
Unrealized Loss, Twelve Months or Longer	(21,913)	(21,525)
Unrealized Loss, Total	(22,923)	(21,629)
Below investment grade [Member] | Corporates [Member] | Other corporate sectors [Member]
Fair Value
Fair Value, Less than Twelve Months	78,721	25,334
Fair Value, Twelve Months or Longer	52,397	54,383
Fair Value, Total	131,118	79,717
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	(7,108)	(5,066)
Unrealized Loss, Twelve Months or Longer	(10,795)	(8,981)
Unrealized Loss, Total	(17,903)	(14,047)
Below investment grade [Member] | Collateralized debt obligations [Member]
Fair Value
Fair Value, Less than Twelve Months	0	0
Fair Value, Twelve Months or Longer	14,177	12,347
Fair Value, Total	14,177	12,347
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	0	0
Unrealized Loss, Twelve Months or Longer	(5,823)	(7,653)
Unrealized Loss, Total	(5,823)	(7,653)
Below investment grade [Member] | Redeemable preferred stocks [Member]
Fair Value
Fair Value, Less than Twelve Months	0	0
Fair Value, Twelve Months or Longer	23,252	24,376
Fair Value, Total	23,252	24,376
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	0	0
Unrealized Loss, Twelve Months or Longer	(3,838)	(2,727)
Unrealized Loss, Total	(3,838)	(2,727)
Below investment grade [Member] | Redeemable preferred stocks [Member] | Financial [Member]
Fair Value
Fair Value, Less than Twelve Months	0	0
Fair Value, Twelve Months or Longer	23,252	24,376
Fair Value, Total	23,252	24,376
Unrealized Loss
Unrealized Loss, Less Than Twelve Months	0	0
Unrealized Loss, Twelve Months or Longer	(3,838)	(2,727)
Unrealized Loss, Total	$ (3,838)	$ (2,727)

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Expected income taxes	$ 47,641	$ 70,674	$ 92,338	$ 137,783
Increase (reduction) in income taxes resulting from:
Low income housing investments	(3,324)	(4,649)	(6,649)	(9,298)
Share-based awards	(2,055)	(4,018)	(4,254)	(9,439)
Other	209	(444)	167	(2,920)
Income tax expense (benefit) from continuing operations	$ 42,471	$ 61,563	$ 81,602	$ 116,126
Expected income taxes	21.00%	35.00%	21.00%	35.00%
Increase (reduction) in income taxes resulting from:
Low income housing investments	(1.50%)	(2.30%)	(1.50%)	(2.40%)
Share-based awards	(0.90%)	(2.00%)	(1.00%)	(2.40%)
Other	0.10%	(0.20%)	0.00%	(0.70%)
Income tax expense (benefit) from continuing operations	18.70%	30.50%	18.50%	29.50%
Tax benefit as a result of remeasuring deferred tax assets and liabilities					$ 877,000

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Letters of credit outstanding	$ 155,000,000	$ 177,000,000
Letter of Credit [Member]
Short-term Debt [Line Items]
Maximum amount of letters of credit available	$ 250,000,000

Liability for Unpaid Claims - S

Liability for Unpaid Claims - Summary of Liability for Unpaid Health Claims (Details) - Health Insurance [Member] - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Activity in the Liability for Unpaid Health Claims
Balance at beginning of period	$ 146,865	$ 143,128
Incurred related to:
Current year	269,574	264,648
Prior years	(5,708)	(8,364)
Total incurred	263,866	256,284
Paid related to:
Current year	171,199	164,271
Prior years	99,054	94,676
Total paid	270,253	258,947
Balance at end of period	$ 140,478	$ 140,465

Liability for Unpaid Claims - R

Liability for Unpaid Claims - Reconciliation of Net Incurred and Paid Claims Development to Liability (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Policy claims and other benefits payable:
Life insurance	$ 188,991	$ 186,429
Total	329,469	333,294
Health Insurance [Member]
Policy claims and other benefits payable:
Total	$ 140,478	$ 146,865

Postretirement Benefits - Summa

Postretirement Benefits - Summary of Post-Retirement Benefit Costs by Component (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5,277	$ 4,484	$ 10,554	$ 8,971
Interest cost	5,493	5,551	10,986	11,101
Expected return on assets	(6,363)	(5,898)	(12,726)	(11,797)
Amortization:
Prior service cost	119	119	238	238
Actuarial (gain) loss	3,636	2,952	7,272	5,903
Direct recognition of expense	0	0	0	0
Net periodic benefit cost	8,162	7,208	16,324	14,416
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	228	250	456	500
Expected return on assets	0	0	0	0
Amortization:
Prior service cost	0	0	0	0
Actuarial (gain) loss	23	38	46	77
Direct recognition of expense	85	116	225	212
Net periodic benefit cost	$ 336	$ 404	$ 727	$ 789

Postretirement Benefits - Pensi

Postretirement Benefits - Pension Assets by Components at Fair Value (Detail) (Details) - Pension Benefits [Member] - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 392,983	$ 377,624
% to Total	100.00%	100.00%
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 189,269	$ 173,356
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	203,714	204,268
Financial [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 46,501	$ 43,451
% to Total	12.00%	12.00%
Financial [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 46,501	$ 43,451
Utilities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 40,032	$ 46,144
% to Total	10.00%	12.00%
Utilities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 40,032	$ 46,144
Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 23,551	$ 25,023
% to Total	6.00%	7.00%
Energy [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 23,551	$ 25,023
Other corporates [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 67,960	$ 65,888
% to Total	17.00%	17.00%
Other corporates [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 67,960	$ 65,888
Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 178,044	$ 180,506
% to Total	45.00%	48.00%
Corporate bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 178,044	$ 180,506
Exchange traded fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 168,743	$ 164,351
% to Total	43.00%	43.00%
Exchange traded fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 168,743	$ 164,351
Other bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 245	$ 256
% to Total	0.00%	0.00%
Other bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 245	$ 256
Other long-term investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 3,998	$ 2,304
% to Total	1.00%	1.00%
Other long-term investments [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 3,998	$ 2,304
Guaranteed annuity contract [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 21,427	$ 21,202
% to Total	5.00%	6.00%
Guaranteed annuity contract [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 21,427	$ 21,202
Short-term investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 18,660	$ 3,984
% to Total	5.00%	1.00%
Short-term investments [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 18,660	$ 3,984
Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 1,866	$ 5,021
% to Total	1.00%	1.00%
Other [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plans-fair value of plan assets	$ 1,866	$ 5,021

Postretirement Benefits - Pen45

Postretirement Benefits - Pension Liability (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liabilities for defined benefit pension plan	$ 595,347	$ 602,606
Qualified plan [Member] | Funded plan [Member] | Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liabilities for defined benefit pension plan	509,965	518,141
Nonqualified plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liabilities for defined benefit pension plan	85,382	84,465
Nonqualified plan [Member] | SERPs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liabilities for defined benefit pension plan	$ 85,382	$ 84,465

Postretirement Benefits - Activ

Postretirement Benefits - Activity for the SERP (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Premiums paid for insurance coverage	$ 1,047	$ 2,050
Liability	595,347	602,606
Nonqualified plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liability	85,382	84,465
SERPs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Total investments	96,923	95,715
SERPs [Member] | Nonqualified plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liability	85,382	84,465
SERP (Active) [Member] | Nonqualified plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liability	82,862	81,457
SERP (Closed) [Member] | Nonqualified plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Liability	2,520	3,008
Company owned life insurance [Member] | SERPs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Total investments	41,872	40,273
Exchange traded fund [Member] | SERPs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Total investments	$ 55,051	$ 55,442

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Basic and Diluted Weighted - Average Shares Outstanding (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Basic weighted average shares outstanding	113,350,175	116,646,669	113,762,340	117,205,467
Weighted average dilutive options outstanding	2,301,237	2,449,882	2,434,633	2,554,158
Diluted weighted average shares outstanding	115,651,412	119,096,551	116,196,973	119,759,625
Antidilutive shares	1,381,686	1,444,280	960,753	1,037,328

Business Segments - Reconciliat

Business Segments - Reconciliation of Segment Operating Information to Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue:
Premium	$ 853,979	$ 816,614	$ 1,704,085	$ 1,637,245
Net investment income	218,568	212,776	436,652	421,058
Other income	416	393	711	809
Total revenue	1,072,963	1,029,783	2,141,448	2,059,112
Expenses:
Policy benefits	568,377	556,415	1,138,266	1,114,191
Required interest on reserves	0	0	0	0
Required interest on DAC	0	0	0	0
Amortization of acquisition costs	129,077	122,121	258,697	248,029
Commissions, premium taxes, and non-deferred acquisition costs	69,427	65,032	139,066	130,148
Insurance administrative expense	55,276	51,412	110,748	103,325
Parent expense	2,847	2,665	5,139	4,898
Stock-based compensation expense	10,497	8,351	19,557	16,546
Interest expense	22,411	21,156	44,033	41,855
Total benefits and expenses	857,912	827,152	1,715,506	1,658,992
Subtotal	215,051	202,631	425,942	400,120
Non-operating items	0	2,094	0	2,094
Measure of segment profitability (pretax)	215,051	204,725	425,942	402,214
Deduct applicable income taxes	(39,991)	(62,543)	(78,712)	(121,361)
Net operating income	175,060	142,182	347,230	280,853
Add back income taxes applicable to segment profitability	39,991	62,543	78,712	121,361
Add (deduct) realized investment gains (losses)	11,813	(705)	13,764	(6,453)
Add (deduct) administrative settlements		(2,094)		(2,094)
Income before income taxes	226,864	201,926	439,706	393,667
Operating Segments [Member] | Life [Member]
Revenue:
Premium	602,534	573,836	1,200,837	1,149,673
Total revenue	602,534	573,836	1,200,837	1,149,673
Expenses:
Policy benefits	399,334	388,765	799,915	779,844
Required interest on reserves	(158,101)	(150,652)	(314,315)	(299,477)
Required interest on DAC	48,275	46,213	96,219	92,149
Amortization of acquisition costs	104,599	98,473	208,376	198,378
Commissions, premium taxes, and non-deferred acquisition costs	47,250	43,708	94,644	87,346
Total benefits and expenses	441,357	426,507	884,839	858,240
Subtotal	161,177	147,329	315,998	291,433
Measure of segment profitability (pretax)	161,177	147,329	315,998	291,433
Operating Segments [Member] | Health [Member]
Revenue:
Premium	251,440	242,775	503,238	487,566
Total revenue	251,440	242,775	503,238	487,566
Expenses:
Policy benefits	160,461	156,579	321,080	314,330
Required interest on reserves	(20,726)	(19,267)	(41,130)	(38,242)
Required interest on DAC	6,079	5,840	12,092	11,649
Amortization of acquisition costs	23,892	23,016	49,149	48,343
Commissions, premium taxes, and non-deferred acquisition costs	22,196	21,351	44,461	42,853
Total benefits and expenses	191,902	187,519	385,652	378,933
Subtotal	59,538	55,256	117,586	108,633
Measure of segment profitability (pretax)	59,538	55,256	117,586	108,633
Operating Segments [Member] | Annuity [Member]
Revenue:
Premium	5	3	10	6
Total revenue	5	3	10	6
Expenses:
Policy benefits	8,582	8,977	17,271	17,923
Required interest on reserves	(11,885)	(12,394)	(23,902)	(24,812)
Required interest on DAC	150	174	303	352
Amortization of acquisition costs	586	632	1,172	1,308
Commissions, premium taxes, and non-deferred acquisition costs	6	7	14	18
Total benefits and expenses	(2,561)	(2,604)	(5,142)	(5,211)
Subtotal	2,566	2,607	5,152	5,217
Measure of segment profitability (pretax)	2,566	2,607	5,152	5,217
Operating Segments [Member] | Investment [Member]
Revenue:
Net investment income	218,568	212,776	436,652	421,058
Total revenue	218,568	212,776	436,652	421,058
Expenses:
Required interest on reserves	190,712	182,313	379,347	362,531
Required interest on DAC	(54,504)	(52,227)	(108,614)	(104,150)
Interest expense	22,411	21,156	44,033	41,855
Total benefits and expenses	158,619	151,242	314,766	300,236
Subtotal	59,949	61,534	121,886	120,822
Measure of segment profitability (pretax)	59,949	61,534	121,886	120,822
Operating Segments [Member] | Other & Corporate [Member]
Revenue:
Other income	441	427	764	878
Total revenue	441	427	764	878
Expenses:
Insurance administrative expense	55,276	51,412	110,748	103,325
Parent expense	2,847	2,665	5,139	4,898
Stock-based compensation expense	10,497	8,351	19,557	16,546
Total benefits and expenses	68,620	62,428	135,444	124,769
Subtotal	(68,179)	(62,001)	(134,680)	(123,891)
Measure of segment profitability (pretax)	(68,179)	(62,001)	(134,680)	(123,891)
Adjustments [Member]
Revenue:
Other income	(25)	(34)	(53)	(69)
Total revenue	(25)	(34)	(53)	(69)
Expenses:
Policy benefits		2,094		2,094
Commissions, premium taxes, and non-deferred acquisition costs	(25)	(34)	(53)	(69)
Insurance administrative expense
Total benefits and expenses	(25)	2,060	(53)	2,025
Subtotal	0	(2,094)	0	(2,094)
Non-operating items	0	2,094	0	2,094
Measure of segment profitability (pretax)	$ 0	$ 0	$ 0	$ 0