Aflac (AFL) 10-Q 30 Apr 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 20, 2020
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-07434
Entity Registrant Name	Aflac Incorporated
Entity Incorporation, State or Country Code	GA
Entity Tax Identification Number	58-1167100
Entity Address, Address Line One	1932 Wynnton Road
Entity Address, City or Town	Columbus,
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	31999
City Area Code	706.
Local Phone Number	323.3431
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		717,507,919
Amendment Flag	false
Entity Central Index Key	0000004977
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2020
NEW YORK STOCK EXCHANGE, INC.
Title of 12(b) Security	Common Stock, $.10 par value per share
Trading Symbol	AFL
Security Exchange Name	NYSE

Consolidated Statements of Earn

Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Revenues:
Net premiums, principally supplemental health insurance	$ 4,681		$ 4,691
Net investment income	904		878
Net investment gains (losses)	(463)		71
Other income (loss)	40		17
Total revenues	5,162		5,657
Benefits and expenses:
Benefits and claims, net	2,939		2,967
Acquisition and operating expenses:
Amortization of deferred policy acquisition costs	333		340
Insurance commissions	336		331
Insurance and other expenses	779	[1]	719
Interest expense	55		58
Total acquisition and operating expenses	1,503		1,448
Total benefits and expenses	4,442		4,415
Earnings before income taxes	720		1,242
Income taxes	154		314
Net earnings	$ 566		$ 928
Net earnings per share:
Basic (in dollars per share)	$ 0.78		$ 1.23
Diluted (in dollars per share)	$ 0.78		$ 1.23
Weighted-average outstanding common shares used in computing earnings per share (In thousands):
Basic (in shares)	724,366		751,423
Diluted (in shares)	727,512		755,790
Cash dividends per share	$ 0.28		$ 0.27
4.00% senior notes paid January 2020
Expense on extinguishment of debt	$ 15
[1]	Includes expense of $15 in 2020 for the early extinguishment of debt

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 566	$ 928
Other comprehensive income (loss) before income taxes:
Unrealized foreign currency translation gains (losses) during period	85	(1)
Unrealized gains (losses) on fixed maturity securities:
Unrealized holding gains (losses) on fixed maturity securities during period	(4,605)	3,196
Reclassification adjustment for (gains) losses on fixed maturity securities included in net earnings	7	(17)
Unrealized gains (losses) on derivatives during period	(4)	(3)
Pension liability adjustment during period	0	7
Total other comprehensive income (loss) before income taxes	(4,517)	3,182
Income tax expense (benefit) related to items of other comprehensive income (loss)	(1,242)	852
Other comprehensive income (loss), net of income taxes	(3,275)	2,330
Total comprehensive income (loss)	$ (2,709)	$ 3,258

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions		Mar. 31, 2020		Dec. 31, 2019
Investments and Cash:
Available for sale, fixed maturity securities		$ 96,288		$ 91,262
Held to maturity, fixed maturity securities, net carrying amount	[1]	23,278
Held to maturity, fixed maturity securities, amortized cost		23,287		30,085
Equity securities		660		802
Commercial mortgage and other loans		10,750		9,569
Other investments		1,843		1,477
Cash and cash equivalents		4,148		4,896
Total investments and cash		136,967		138,091
Receivables		813		828
Accrued investment income		734		772
Deferred policy acquisition costs		10,164		10,128
Property and equipment, at cost less accumulated depreciation		586		581
Other		2,352		2,368
Total assets		151,616		152,768
Policy Liabilities:
Future policy benefits		91,393		90,335
Unpaid policy claims		4,693		4,659
Unearned premiums		4,044		4,243
Other policyholders’ funds		7,422		7,317
Total policy liabilities		107,552		106,554
Income taxes		4,610		5,370
Payables for return of cash collateral on loaned securities		2,969		1,876
Notes payable and lease obligations		6,758		6,569
Other		3,325		3,440
Total liabilities		125,214		123,809
Commitments and contingent liabilities (Note 13)
Shareholders’ equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2020 and 2019; issued 1,350,650 shares in 2020 and 1,349,309 shares in 2019		135		135
Additional paid-in capital		2,334		2,313
Retained earnings		34,599		34,291
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)		(1,543)		(1,623)
Unrealized gain (losses) on fixed maturity securities		6,043		8,548
Unrealized gains (losses) on derivatives		(35)		(33)
Pension liability adjustment		(277)		(277)
Treasury stock, at average cost		(14,854)		(14,395)
Total shareholders’ equity		26,402		28,959
Total liabilities and shareholders’ equity		151,616		152,768
Consolidated Entity Excluding Variable Interest Entities (VIE)
Investments and Cash:
Available for sale, fixed maturity securities		92,502		86,950
Variable Interest Entity, Consolidated
Investments and Cash:
Available for sale, fixed maturity securities		3,786		4,312
Commercial mortgage and other loans		9,051		7,956
Other investments	[2]	550		494
Policy Liabilities:
Total liabilities		$ 235	[3]	$ 126
[1]	Net of allowance for credit losses
[2]	Consists entirely of alternative investments in limited partnerships
[3]	Net of allowance for credit losses

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions		Mar. 31, 2020		Dec. 31, 2019
Available for sale, fixed maturity securities, amortized cost		$ 87,881		$ 79,371
Available for sale, fixed maturity securities, allowance for credit losses		63
Held to maturity, fixed maturity securities, fair value		29,347		37,594
Held-to-maturity, fixed maturity securities, allowance for credit losses		9
Commercial mortgage and other loans		10,750		9,569
Commercial mortgage and other loans, allowance for credit losses		125		45	[1]
Other investments		$ 1,843		$ 1,477
Common stock, par value (in dollars per share)		$ 0.10		$ 0.10
Common stock, shares authorized (in shares)		1,900,000		1,900,000
Common stock, shares issued (in shares)		1,350,650		1,349,309
Consolidated Entity Excluding Variable Interest Entities (VIE)
Available for sale, fixed maturity securities, amortized cost		$ 84,673		$ 76,063
Available for sale, fixed maturity securities, allowance for credit losses		63
Variable Interest Entity, Consolidated
Available for sale, fixed maturity securities, amortized cost		3,208	[2]	3,308
Commercial mortgage and other loans		9,051		7,956
Other investments	[3]	$ 550		$ 494
[1]	U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
[2]	Net of allowance for credit losses
[3]	Consists entirely of alternative investments in limited partnerships

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Millions		Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock
Balance, beginning of period at Dec. 31, 2018		$ 23,462	$ 135	$ 2,177	$ 31,788	$ 2,151	$ (12,789)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		928	0	0	928	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(1)	0	0	0	(1)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		2,327	0	0	0	2,327	0
Unrealized gains (losses) on derivatives during period, net of income taxes		(2)	0	0	0	(2)	0
Pension liability adjustment during period, net of income taxes		6	0	0	0	6	0
Dividends to shareholders		(203)	0	0	(203)	0	0
Exercise of stock options		11	0	11	0	0	0
Share-based compensation		8	0	8	0	0	0
Purchases of treasury stock		(517)	0	0	0	0	(517)
Treasury stock reissued		30	0	12	0	0	18
Balance, end of period at Mar. 31, 2019		26,049	135	2,208	32,513	4,481	(13,288)
Balance, beginning of period at Dec. 31, 2019		28,959	135	2,313	34,291	6,615	(14,395)
Cumulative effect of change in accounting principle, net of income taxes (Accounting Standards Update 2016-13) at Dec. 31, 2019	[1]	(56)	0	0	(56)	0	0
Cumulative effect of change in accounting principle, net of income taxes (Accounting Standards Update 2019-04) at Dec. 31, 2019	[1]	848	0	0	0	848	0
Adjusted balance, beginning of period at Dec. 31, 2019		29,751	135	2,313	34,235	7,463	(14,395)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		566	0	0	566	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		80	0	0	0	80	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		(3,353)	0	0	0	(3,353)	0
Unrealized gains (losses) on derivatives during period, net of income taxes		(2)	0	0	0	(2)	0
Pension liability adjustment during period, net of income taxes		0	0	0	0	0	0
Dividends to shareholders		(202)	0	0	(202)	0	0
Exercise of stock options		5	0	5	0	0	0
Share-based compensation		7	0	7	0	0	0
Purchases of treasury stock		(476)	0	0	0	0	(476)
Treasury stock reissued		26	0	9	0	0	17
Balance, end of period at Mar. 31, 2020		$ 26,402	$ 135	$ 2,334	$ 34,599	$ 4,188	$ (14,854)
[1]	See Note 1 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance on January 1, 2020

Consolidated Statements of Sh_2

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Retained earnings
Dividends to shareholders (in dollars per share)	$ 0.28	$ 0.27

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net earnings	$ 566	$ 928
Adjustments to reconcile net earnings to net cash provided by operating activities:
Change in receivables and advance premiums	15	35
Capitalization of deferred policy acquisition costs	(325)	(357)
Amortization of deferred policy acquisition costs	333	340
Increase in policy liabilities	368	468
Change in income tax liabilities	153	316
Realized investment (gains) losses	463	(71)
Other, net	(159)	(115)
Net cash provided (used) by operating activities	1,414	1,544
Proceeds from investments sold or matured:
Available-for-sale fixed maturity securities	726	760
Equity securities	3	153
Held-to-maturity fixed maturity securities	0	155
Commercial mortgage and other loans	408	493
Costs of investments acquired:
Available for sale fixed maturity securities	(1,817)	(2,548)
Equity securities	(6)	(151)
Commercial mortgage and other loans	(1,787)	(669)
Other investments, net	(361)	(442)
Settlement of derivatives, net	13	(3)
Cash received (pledged or returned) as collateral, net	1,160	976
Other, net	(55)	(15)
Net cash provided (used) by investing activities	(1,716)	(1,291)
Cash flows from financing activities:
Purchases of treasury stock	(449)	(490)
Proceeds from borrowings	545	0
Principal payments under debt obligations	(350)	0
Dividends paid to shareholders	(195)	(195)
Change in investment-type contracts, net	(5)	(13)
Treasury stock reissued	9	12
Other, net	(1)	0
Net cash provided (used) by financing activities	(446)	(686)
Effect of exchange rate changes on cash and cash equivalents	0	(12)
Net change in cash and cash equivalents	(748)	(445)
Cash and cash equivalents, beginning of period	4,896	4,337
Cash and cash equivalents, end of period	4,148	3,892
Supplemental disclosures of cash flow information:
Income taxes paid	2	(2)
Interest paid	39	36
Noncash interest	15	22
Noncash financing activities:
Lease obligations	13	1
Associate stock bonus
Treasury stock issued for:
Treasury stock issued	5	6
Shareholder dividend reinvestment
Treasury stock issued for:
Treasury stock issued	7	8
Share-based compensation grants
Treasury stock issued for:
Treasury stock issued	$ 5	$ 4

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Description of Business Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) primarily sell supplemental health and life insurance in the United States (U.S.) and Japan. The Company’s operations consist of two reportable business segments: Aflac Japan and Aflac U.S. The Parent Company's primary insurance subsidiaries are Aflac Life Insurance Japan Ltd. (Aflac Japan) and American Family Life Assurance Company of Columbus (Aflac); Continental American Insurance Company (CAIC), branded as Aflac Group Insurance (AGI); American Family Life Assurance Company of New York (Aflac New York); Tier One Insurance Company (TOIC) and Argus Dental & Vision, Inc (Argus), which provides a platform for Aflac Dental and Vision in the U.S. (collectively, Aflac U.S.). Aflac Japan's revenues, including net gains and losses on its investment portfolio, accounted for 67% and 68% of the Company's total revenues in the three -month periods ended March 31, 2020 and 2019 , respectively. The percentage of the Company's total assets attributable to Aflac Japan was 84% at March 31, 2020 and December 31, 2019 , respectively. Basis of Presentation The Company prepares its financial statements in accordance with U.S. generally accepted accounting principles (U.S. GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to U.S. GAAP issued by the FASB are derived from the FASB Accounting Standards Codification TM (ASC). The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates based on currently available information when recording transactions resulting from business operations. The most significant items on the Company's balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments and derivatives, deferred policy acquisition costs (DAC), liabilities for future policy benefits and unpaid policy claims, and income taxes. These accounting estimates and actuarial determinations are sensitive to market conditions, investment yields, mortality, morbidity, commission and other acquisition expenses, and terminations by policyholders. As additional information becomes available, or actual amounts are determinable, the recorded estimates will be revised and reflected in operating results. Although some variability is inherent in these estimates, the Company believes the amounts provided are adequate. The unaudited consolidated financial statements include the accounts of the Parent Company, its subsidiaries and those entities required to be consolidated under applicable accounting standards. All material intercompany accounts and transactions have been eliminated. In the opinion of management, the accompanying unaudited consolidated financial statements of the Company contain all adjustments, consisting of normal recurring accruals, which are necessary to fairly present the consolidated balance sheets as of March 31, 2020 , and December 31, 2019 , and the consolidated statements of earnings and comprehensive income (loss), shareholders' equity and cash flows for the three -month periods ended March 31, 2020 and 2019 . Results of operations for interim periods are not necessarily indicative of results for the entire year. As a result, these financial statements should be read in conjunction with the financial statements and notes thereto included in the Company's annual report on Form 10-K for the year ended December 31, 2019 ( 2019 Annual Report). COVID-19: On March 11, 2020, the World Health Organization declared the COVID-19 outbreak a global pandemic. The impact of COVID-19 on the Company is evolving and its future effects are uncertain and the Company is closely monitoring the effects and risks of COVID-19 to assess its impact on the Company's business, financial condition, results of operations, liquidity and capital position. Liquidity and Capital Resources The Company entered the crisis having maintained capital ratios in Japan and the U.S. at a level designed to absorb a degree of market volatility. To further support liquidity and capital resources, the Parent Company, in March 2020, issued four series of senior notes totaling ¥57.0 billion and, in April 2020, issued $1 billion in senior notes through public debt offerings under its U.S. shelf registration statement. The Company has available liquidity in its unsecured revolving credit facilities of $1.0 billion and ¥100.0 billion , respectively, and currently has no borrowings under either of these facilities. In April 2020, Aflac increased its internal limit for Federal Home Loan Bank of Atlanta (FHLB) borrowings to $800 million , $300 million of which the Company has designated to be used for short-term liquidity needs and subject to qualified collateral availability and other conditions. The Company continues to evaluate other sources of liquidity including reinvestment cash flows and selling investments. Major government initiatives Government authorities in Japan and the U.S. have implemented several initiatives in response to the COVID-19 pandemic, including actions designed to mitigate the adverse health effects of the virus and those designed to provide broad-based relief and economic support to all aspects of the economy. Given that these measures were recently implemented, it is too early to determine what impacts these initiatives will have on the Company’s business, results of operations, financial condition, liquidity, capital position, investment portfolio, workforce, distribution partners and vendors. Reclassifications : Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. These reclassifications had no impact on net earnings or total shareholders' equity. New Accounting Pronouncements Recently Adopted Accounting Pronouncements Standard Description Date of Adoption Effect on Financial Statements or Other Significant Matters Accounting Standards Update (ASU) 2019-04 Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments In April 2019, the FASB issued Codification improvements to clarify and correct certain areas of guidance amended as part of ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2016-13 , Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments; and ASU 2017-12 , Derivative and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. The most significant of these improvements to the Company was related to the Codification improvement to ASU 2017-12 and the clarification that a one-time reclassification of assets that are eligible to be hedged under the last-of-layer method (i.e., certain pre-payable securities) from held-to-maturity to available-for-sale is allowed under the new hedge accounting guidance and would not impact the Company’s ability to continue to classify other bonds as held-to-maturity. The other amendments related to ASU 2017-12 and 2016-01 are either not significant, or were previously implemented as part of the related ASU adoptions. Applicable amendments related to ASU 2016-13 are discussed within the recent adoption of that update below. January 1, 2020 The adoption of this guidance resulted in a reclassification of $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity to the available-for-sale category. The reclassification resulted in recording in accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis, based on the securities’ fair values on the reclassification date. The reclassification impacted the adoption of ASU 2016-13 (see ASU 2016-13 below for additional details). ASU 2018-17 Consolidation: Targeted Improvements to Related Party Guidance for Variable Interest Entities In October 2018, the FASB issued targeted improvements which provide that indirect interests held through related parties under common control should be considered on a proportional basis for determining whether fees paid to decision makers and service providers are variable interests. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2018-13 Fair Value Measurement, Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued amendments to the disclosure requirements on fair value measurements. The amendments remove, modify, and add certain disclosures. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company’s financial position, results of operations, or disclosures. Standard Description Date of Adoption Effect on Financial Statements or Other Significant Matters ASU 2017-04 Intangibles - Goodwill and Other: Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued amendments simplifying the subsequent measurement of goodwill. An entity, under this update, is no longer required to perform a hypothetical purchase price allocation to measure goodwill impairment. Instead, the entity should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2016-13 Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments as clarified and amended by: ASU 2019-04 , Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, ASU 2019-05 , Financial Instruments - Credit Losses (Topic 326), Targeted Transition Relief and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments- Credit Losses In June 2016, the FASB issued amendments that require a financial asset (or a group of financial assets) measured at amortized cost to be presented net of an allowance for credit losses (Credit Losses ASU) in order to reflect the amount expected to be collected on the financial asset(s). The measurement of expected credit losses is amended by replacing the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information. Credit losses on available-for-sale debt securities will be measured in a manner similar to current U.S. GAAP; however, the amendments require that credit losses be presented as an allowance rather than as a write-down. Other amendments include changes to the balance sheet presentation and interest income recognition of purchased financial assets with a more-than-insignificant credit deterioration since origination (PCD financial assets). January 1, 2020 The Company recorded a cumulative effect adjustment with a decrease to beginning 2020 retained earnings of $56 million, net of taxes. See Note 3 of the Notes to the Consolidated Financial Statements for credit loss disclosures. The following line items in the consolidated balance sheets were most significantly impacted by the adoption of the new accounting standard: • Fixed maturity securities held to maturity, at amortized cost • Commercial mortgage and other loans • Reinsurance recoverable, included within Other assets Accounting Pronouncements Pending Adoption Standard Description Effect on Financial Statements or Other Significant Matters ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting In March 2020, the FASB issued amendments that provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this ASU only apply to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. An entity may elect to apply the amendments as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. The Company is thoroughly evaluating the adoption of this guidance and the impact on the Company’s financial position, results of operations, and disclosures. ASU 2020-01 Clarifying the interactions between Topic 321, Topic 323, and Topic 815 In January 2020, the FASB issued amendments clarifying that an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting for the purposes of applying the measurement alternative in accordance with Topic 321 immediately before applying or upon discontinuing the equity method. In addition, the amendments clarify that for the purpose of applying certain derivative guidance in Topic 815, an entity should not consider whether, upon the settlement of the forward contract or exercise of the purchased option, individually or with existing investments, the underlying securities would be accounted for under the equity method in Topic 323 or the fair value option in accordance with the financial instruments guidance in Topic 825. An entity also would evaluate the remaining characteristics in Topic 815 to determine the accounting for those forward contracts and purchased options. The amendments are effective for public business entities for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. Early adoption is permitted. The adoption of this guidance is not expected to have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2018-12 Financial Services - Insurance, Targeted Improvements to the Accounting for Long-Duration Contracts as clarified and amended by: ASU 2019-09 Financial Services - Insurance (Topic 944): Effective Date In August 2018, the FASB issued amendments that will significantly change how insurers account for long-duration contracts. The amendments will change existing recognition, measurement, presentation, and disclosure requirements. Issues addressed in the new guidance include: 1) a requirement to review and, if there is a change, update assumptions for the liability for future policy benefits at least annually, and to update the discount rate assumption quarterly, 2) accounting for market risk benefits at fair value, 3) simplified amortization for deferred acquisition costs, and 4) enhanced financial statement presentation and disclosures. The amendments are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. In November 2019, the FASB issued an amendment extending the effective date for public business entities that meet the definition of an SEC filer, excluding entities eligible to be small reporting companies as defined by the SEC, by one year. The amendments are now effective for the Company for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021. Early application of the amendments is permitted. The Company is thoroughly evaluating the impact of adoption and expects that the adoption will have a significant impact on the Company’s financial position, results of operations, and disclosures. The Company anticipates that the requirement to update assumptions for liability for future policy benefits will have a significant impact on its results of operations, systems, processes and controls while the requirement to update the discount rate will have a significant impact on its equity. The Company has no products with market risk benefits. The Company does not expect to early adopt the updated standard and has tentatively selected a modified retrospective transition method. Recent accounting guidance not discussed above is not applicable, did not have, or is not expected to have a material impact to the Company's business. For additional information on new accounting pronouncements and recent accounting guidance and their impact, if any, on the Company's financial position, results of operations or disclosures, see Note 1 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report.

BUSINESS SEGMENT INFORMATION

BUSINESS SEGMENT INFORMATION	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
BUSINESS SEGMENT INFORMATION	BUSINESS SEGMENT INFORMATION The Company consists of two reportable insurance business segments: Aflac Japan and Aflac U.S., both of which sell supplemental health and life insurance. In addition, operating business units that are not individually reportable and business activities, including reinsurance retrocession activities, not included in Aflac Japan or Aflac U.S. are included in Corporate and other. The Company does not allocate corporate overhead expenses to business segments. Consistent with U.S. GAAP accounting guidance for segment reporting, the Company evaluates and manages its business segments using a financial performance measure called pretax adjusted earnings. Adjusted earnings are adjusted revenues less benefits and adjusted expenses. The adjustments to both revenues and expenses account for certain items that cannot be predicted or that are outside management’s control. Adjusted revenues are U.S. GAAP total revenues excluding net investment gains and losses, except for amortized hedge costs/income related to foreign currency exposure management strategies and net interest cash flows from derivatives associated with certain investment strategies. Adjusted expenses are U.S. GAAP total acquisition and operating expenses including the impact of interest cash flows from derivatives associated with notes payable but excluding any nonrecurring or other items not associated with the normal course of the Company’s insurance operations and that do not reflect Aflac’s underlying business performance. The Company excludes income taxes related to operations to arrive at pretax adjusted earnings. Information regarding operations by reportable segment and Corporate and other, follows: Three Months Ended (In millions) 2020 2019 Revenues: Aflac Japan: Net earned premiums $ 3,150 $ 3,180 Adjusted net investment income (1),(2) 642 610 Other income 11 12 Total adjusted revenue Aflac Japan 3,803 3,802 Aflac U.S.: Net earned premiums 1,483 1,461 Net investment income 177 177 Other income 27 2 Total adjusted revenue Aflac U.S. 1,687 1,640 Corporate and other (3) 104 95 Total adjusted revenues 5,594 5,537 Net investment gains (losses) (1),(2),(3) (432 ) 120 Total revenues $ 5,162 $ 5,657 (1) Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations. (2) Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income. (3) Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations. Three Months Ended (In millions) 2020 2019 Pretax adjusted earnings: Aflac Japan (1),(2) $ 855 $ 834 Aflac U.S. 326 323 Corporate and other (3),(4) 2 (18 ) Pretax adjusted earnings (5) 1,183 1,139 Net investment gains (losses) (1),(2),(3),(4) (448 ) 103 Other income (loss) (15 ) 0 Total earnings before income taxes $ 720 $ 1,242 Income taxes applicable to pretax adjusted earnings $ 301 $ 291 Effect of foreign currency translation on after-tax 9 (8 ) (1) Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations. (2) Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income. (3) Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase in net investment income when analyzing operations. (4) A gain of $16 and $17 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations. (5) Includes $33 for the three-month periods ended March 31, 2020 , and 2019 , respectively, of interest expense on debt. Assets were as follows: (In millions) March 31, December 31, Assets: Aflac Japan $ 126,955 $ 127,523 Aflac U.S. 20,526 20,945 Corporate and other 4,135 4,300 Total assets $ 151,616 $ 152,768

INVESTMENTS

INVESTMENTS	3 Months Ended
	Mar. 31, 2020
Investments [Abstract]
INVESTMENTS	INVESTMENTS Investment Holdings The amortized cost for the Company's investments in fixed maturity securities, the cost for equity securities and the fair values of these investments are shown in the following tables. March 31, 2020 (In millions) Allowance for Credit Losses Gross Gross Fair Securities available for sale, carried at fair Fixed maturity securities: Yen-denominated: Japan government and agencies $ 31,853 $ 0 $ 4,766 $ 14 $ 36,605 Municipalities 984 0 228 1 1,211 Mortgage- and asset-backed securities 306 0 31 0 337 Public utilities 4,412 0 430 93 4,749 Sovereign and supranational 1,300 0 33 27 1,306 Banks/financial institutions 7,159 0 404 557 7,006 Other corporate 7,817 0 753 389 8,181 Total yen-denominated 53,831 0 6,645 1,081 59,395 U.S. dollar-denominated: U.S. government and agencies 350 0 23 0 373 Municipalities 1,084 0 145 0 1,229 Mortgage- and asset-backed securities 152 0 8 0 160 Public utilities 3,844 0 649 50 4,443 Sovereign and supranational 239 0 65 1 303 Banks/financial institutions 2,848 0 545 21 3,372 Other corporate 25,533 63 2,531 988 27,013 Total U.S. dollar-denominated 34,050 63 3,966 1,060 36,893 Total securities available for sale $ 87,881 $ 63 $ 10,611 $ 2,141 $ 96,288 December 31, 2019 (In millions) Gross Gross Fair Securities available for sale, carried at fair value through other comprehensive income: Fixed maturity securities: Yen-denominated: Japan government and agencies $ 30,929 $ 5,169 $ 0 $ 36,098 Municipalities 516 116 3 629 Mortgage- and asset-backed securities 229 25 0 254 Public utilities 1,855 406 0 2,261 Sovereign and supranational 680 50 0 730 Banks/financial institutions 6,152 700 86 6,766 Other corporate 5,323 944 24 6,243 Total yen-denominated 45,684 7,410 113 52,981 U.S dollar-denominated: U.S. government and agencies 293 9 0 302 Municipalities 1,077 141 0 1,218 Mortgage- and asset-backed securities 149 7 0 156 Public utilities 3,804 725 10 4,519 Sovereign and supranational 239 73 0 312 Banks/financial institutions 2,879 646 4 3,521 Other corporate 25,246 3,255 248 28,253 Total U.S. dollar-denominated 33,687 4,856 262 38,281 Total securities available for sale $ 79,371 $ 12,266 $ 375 $ 91,262 March 31, 2020 (In millions) Allowance for Credit Losses Net Carrying Amount Gross Gross Fair Securities held to maturity, carried at Fixed maturity securities: Yen-denominated: Japan government and agencies $ 22,387 $ 3 $ 22,384 $ 5,810 $ 0 $ 28,194 Municipalities 362 0 362 122 0 484 Public utilities 46 1 45 14 0 59 Sovereign and supranational 469 5 464 114 0 578 Other corporate 23 0 23 9 0 32 Total yen-denominated 23,287 9 23,278 6,069 0 29,347 Total securities held to maturity $ 23,287 $ 9 $ 23,278 $ 6,069 $ 0 $ 29,347 December 31, 2019 (In millions) Gross Gross Fair Securities held to maturity, carried at Fixed maturity securities: Yen-denominated: Japan government and agencies $ 22,241 $ 6,050 $ 0 $ 28,291 Municipalities 821 262 0 1,083 Mortgage- and asset-backed securities 16 1 0 17 Public utilities 2,535 419 0 2,954 Sovereign and supranational 1,123 197 0 1,320 Banks/financial institutions 916 105 3 1,018 Other corporate 2,433 485 7 2,911 Total yen-denominated 30,085 7,519 10 37,594 Total securities held to maturity $ 30,085 $ 7,519 $ 10 $ 37,594 (In millions) March 31, 2020 December 31, 2019 Equity securities, carried at fair value through net earnings: Fair Value Fair Value Equity securities: Yen-denominated $ 528 $ 658 U.S. dollar-denominated 132 144 Total equity securities $ 660 $ 802 The methods of determining the fair values of the Company's investments in fixed maturity securities and equity securities are described in Note 5. During the first quarter of 2020, as a result of the adoption of ASU 2019-04 discussed in Note 1, the Company reclassified $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity category to the available-for-sale category. This reclassification resulted in recording in accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis . During the first quarter of 2019, the Company did not reclassify any investments from the held-to-maturity category to the available-for-sale category. Contractual and Economic Maturities The contractual and economic maturities of the Company's investments in fixed maturity securities at March 31, 2020 , were as follows: (In millions) Amortized (1) Fair Available for sale: Due in one year or less $ 1,078 $ 1,105 Due after one year through five years 8,992 8,806 Due after five years through 10 years 12,399 13,221 Due after 10 years 64,891 72,659 Mortgage- and asset-backed securities 458 497 Total fixed maturity securities available for sale $ 87,818 $ 96,288 Held to maturity: Due in one year or less $ 0 $ 0 Due after one year through five years 0 0 Due after five years through 10 years 49 55 Due after 10 years 23,229 29,292 Mortgage- and asset-backed securities 0 0 Total fixed maturity securities held to maturity $ 23,278 $ 29,347 (1) Net of allowance for credit losses Economic maturities are used for certain debt instruments with no stated maturity where the expected maturity date is based on the combination of features in the financial instrument such as the right to call or prepay obligations or changes in coupon rates. Investment Concentrations The Company's process for investing in credit-related investments begins with an independent approach to underwriting each issuer's fundamental credit quality. The Company evaluates independently those factors that it believes could influence an issuer's ability to make payments under the contractual terms of the Company's instruments. This includes a thorough analysis of a variety of items including the issuer's country of domicile (including political, legal, and financial considerations); the industry in which the issuer competes (with an analysis of industry structure, end-market dynamics, and regulation); company specific issues (such as management, assets, earnings, cash generation, and capital needs); and contractual provisions of the instrument (such as financial covenants and position in the capital structure). The Company further evaluates the investment considering broad business and portfolio management objectives, including asset/liability needs, portfolio diversification, and expected income. Investment exposures that individually exceeded 10% of shareholders' equity were as follows: March 31, 2020 December 31, 2019 (In millions) Credit Amortized Fair Credit Amortized Fair Japan National Government (1) A+ $52,786 $63,020 A+ $51,726 $62,584 (1) Japan Government Bonds (JGBs) or JGB-backed securities Net Investment Gains and Losses Information regarding pretax net gains and losses from investments is as follows: Three Months Ended (In millions) 2020 2019 Net investment gains (losses): Sales and redemptions: Fixed maturity securities available for sale: Gross gains from sales $ 7 $ 12 Gross losses from sales 0 (8 ) Foreign currency gains (losses) on sales and redemptions (14 ) 13 Total sales and redemptions (7 ) 17 Equity securities (149 ) 58 Loan loss reserves (1) 0 (2 ) Credit losses: Fixed maturity securities available for sale (63 ) 0 Fixed maturity securities held to maturity 1 0 Commercial mortgage and other loans (37 ) 0 Loan commitments (46 ) 0 Total credit losses (145 ) 0 Derivatives and other: Derivative gains (losses) (85 ) 0 Foreign currency gains (losses) (77 ) (2 ) Total derivatives and other (162 ) (2 ) Total net investment gains (losses) $ (463 ) $ 71 (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only. The unrealized holding gains , net of losses , recorded as a component of net investment gains and losses for the three -month period ended March 31, 2020 , that relate to equity securities still held at the March 31, 2020 reporting date, were $149 million . Unrealized Investment Gains and Losses Effect on Shareholders’ Equity The net effect on shareholders’ equity of unrealized gains and losses from fixed maturity securities was as follows: (In millions) March 31, 2020 December 31, Unrealized gains (losses) on securities available for sale $ 8,470 $ 11,891 Deferred income taxes (2,427 ) (3,343 ) Shareholders’ equity, unrealized gains (losses) on fixed maturity securities $ 6,043 $ 8,548 Gross Unrealized Loss Aging The following tables show the fair values and gross unrealized losses of the Company's available-for-sale investments for the periods ended March 31, 2020 and available-for-sale and held-to-maturity investments for prior periods that were in an unrealized loss position, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position. March 31, 2020 Total Less than 12 months 12 months or longer (In millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed maturity securities available Japan government and Yen-denominated $ 725 $ 14 $ 725 $ 14 $ 0 $ 0 Municipalities: Yen-denominated 56 1 42 0 14 1 Public utilities: U.S. dollar-denominated 825 50 701 38 124 12 Yen-denominated 880 93 880 93 0 0 Sovereign and supranational: U.S. dollar-denominated 18 1 18 1 0 0 Yen-denominated 701 27 701 27 0 0 Banks/financial institutions: U.S. dollar-denominated 355 21 321 13 34 8 Yen-denominated 3,410 557 2,626 406 784 151 Other corporate: U.S. dollar-denominated 8,244 988 5,427 527 2,817 461 Yen-denominated 2,829 389 2,677 357 152 32 Total $ 18,043 $ 2,141 $ 14,118 $ 1,476 $ 3,925 $ 665 December 31, 2019 Total Less than 12 months 12 months or longer (In millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed maturity securities: Municipalities: Yen-denominated $ 80 $ 3 $ 80 $ 3 $ 0 $ 0 Public utilities: U.S. dollar-denominated 306 10 69 2 237 8 Banks/financial institutions: U.S. dollar-denominated 79 4 18 0 61 4 Yen-denominated 1,828 89 1,828 89 0 0 Other corporate: U.S. dollar-denominated 4,261 248 792 53 3,469 195 Yen-denominated 636 31 636 31 0 0 Total $ 7,190 $ 385 $ 3,423 $ 178 $ 3,767 $ 207 Analysis of Securities in Unrealized Loss Positions The unrealized losses on the Company's fixed maturity securities investments have been primarily related to general market changes in interest rates, foreign exchange rates, and/or the levels of credit spreads rather than specific concerns with the issuer's ability to pay interest and repay principal. For any significant declines in fair value of its fixed maturity securities, the Company performs a more focused review of the related issuers' credit profile. For corporate issuers, the Company evaluates their assets, business profile including industry dynamics and competitive positioning, financial statements and other available financial data. For non-corporate issuers, the Company analyzes all sources of credit support, including issuer-specific factors. The Company utilizes information available in the public domain and, for certain private placement issuers, from consultations with the issuers directly. The Company also considers ratings from Nationally Recognized Statistical Rating Organizations (NRSROs), as well as the specific characteristics of the security it owns including seniority in the issuer's capital structure, covenant protections, or other relevant features. From these reviews, the Company evaluates the issuers' continued ability to service the Company's investment through payment of interest and principal. Assuming no credit-related factors develop, unrealized gains and losses on fixed maturity securities are expected to diminish as investments near maturity. Based on its credit analysis, the Company believes that the issuers of its fixed maturity investments in the sectors shown in the table above have the ability to service their obligations to the Company, and the Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases, which may be at maturity. However, the Company has identified certain available-for-sale fixed maturity securities where the amortized cost basis exceeds the present value of the cash flows expected to be collected due to credit related factors and as a result, a credit allowance has been calculated. As of March 31, 2020, the Company recorded an allowance of $63 million . Refer to the Credit Losses section below for additional information. Commercial Mortgage and Other Loans The Company classifies its transitional real estate loans (TREs), commercial mortgage loans (CMLs) and middle market loans (MMLs) as held-for-investment and includes them in the commercial mortgage and other loans line on the consolidated balance sheets. The Company carries them on the balance sheet at amortized cost less an estimated allowance for credit losses. The following table reflects the composition of the carrying value for commercial mortgage and other loans by property type as of the periods presented. (In millions) March 31, 2020 December 31, 2019 Amortized Cost % of Total Amortized Cost % of Total Commercial Mortgage and other loans: Transitional real estate loans: Office $ 1,954 18.0 % $ 1,800 18.7 % Retail 165 1.5 131 1.4 Apartments/Multi-Family 2,065 19.0 2,085 21.7 Industrial 175 1.6 256 2.7 Hospitality 1,024 9.4 1,036 10.8 Other 260 2.4 164 1.7 Total transitional real estate loans 5,643 51.9 5,472 57.0 Commercial mortgage loans: Office 408 3.8 410 4.3 Retail 346 3.1 348 3.5 Apartments/Multi-Family 589 5.4 569 5.9 Industrial 397 3.7 383 4.0 Total commercial mortgage loans 1,740 16.0 1,710 17.7 Middle market loans 3,492 32.1 2,432 25.3 Total commercial mortgage and other loans $ 10,875 100.0 % $ 9,614 100.0 % Allowance for credit losses (125 ) (45 ) (1) Total net commercial mortgage and other loans $ 10,750 $ 9,569 (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only. Commercial mortgage and transitional real estate loans were secured by properties entirely within the U.S. (with the largest concentrations in California ( 20% ), Texas ( 14% ) and Florida ( 10% )). Middle market loans are issued only to companies domiciled within the U.S. and Canada. Transitional Real Estate Loans Transitional real estate loans are commercial mortgage loans that are typically relatively short-term floating rate instruments secured by a first lien on the property. These loans provide funding for properties undergoing a change in their physical characteristics and/or economic profile and do not typically require any principal repayment prior to the maturity date. This loan portfolio is generally considered to be investment grade. As of March 31, 2020 , the Company had $838 million in outstanding commitments to fund transitional real estate loans. These commitments are contingent on the final underwriting and due diligence to be performed. Commercial Mortgage Loans Commercial mortgage loans are typically fixed rate loans on commercial real estate with partial repayment of principal over the life of the loan with the remaining outstanding principal being repaid upon maturity. This loan portfolio is generally considered higher quality investment grade loans. As of March 31, 2020 , the Company had $10 million of outstanding commitments to fund commercial mortgage loans. These commitments are contingent on the final underwriting and due diligence to be performed. Middle Market Loans Middle market loans are typically first lien senior secured cash flow loans to small to mid-size companies for working capital, refinancing, acquisition, and recapitalization. These loans are generally considered to be below investment grade. The carrying value for middle market loans included $99 million for a short term credit facility that is reflected in other liabilities on the consolidated balance sheets, as of December 31, 2019 . The carrying value for middle market loans did not include any amount for a short term credit facility as of March 31, 2020. As of March 31, 2020 , the Company had commitments of approximately $2.6 billion of which $2.2 billion was a result of a new agreement with an external manager during the first quarter of 2020 to fund future middle market loans. These commitments are contingent upon the availability of middle market loans that meet the Company's underwriting criteria. Credit Losses Effective January 1, 2020, the Company adopted ASC 326: Financial Instruments - Credit Losses . The newly adopted accounting standard requires the Company to estimate an expected lifetime credit loss on financial assets including short-term receivables, held-to-maturity fixed maturity securities, loan receivables, loan commitments and reinsurance recoverables. For the Company’s available-for-sale fixed maturity securities, the newly adopted guidance requires an entity to evaluate estimated credit losses only when the fair value of the available-for-sale fixed maturity security is below its amortized cost basis. Credit loss changes are recorded as a component of net investment gains and losses for the Company’s held-to-maturity and available-for-sale securities, loan receivables, loan commitments and reinsurance recoverables. The Company’s off-balance sheet credit exposure is primarily attributable to loan commitments that are not unconditionally cancelable. The Company considers the contractual period of exposure to credit risk, the likelihood that funding will occur, the risk of loss, and the current conditions and expectations of future economic conditions to develop the estimate of expected credit losses. The Company records the estimate of expected credit losses for certain loan commitments within other liabilities in the consolidated balance sheet. Write-offs and partial write-offs are recorded as a reduction to the amortized cost of the loan or fixed maturity security balance and a reduction to the credit allowance. The Company’s held-to-maturity fixed maturity portfolio includes Japan Government and Agency securities of $22 billion amortized cost as of March 31, 2020 that meet the requirements for zero-credit-loss expectation and therefore these asset classes have been excluded from the current expected credit loss measurement. The Company has elected not to measure an allowance on accrued interest income for all asset types, because the uncollectible accrued interest receivable is written off in a timely manner. The Company writes off accrued interest when it is more than ninety days past due. The Company has elected to write off accrued interest by reversing interest income, which is a component of net investment income, in the consolidated statement of earnings. The Company designates nonaccrual status for a nonperforming debt security or a loan that is not generating its stated interest rate because of nonpayment of periodic interest by the borrower. The Company applies the cash basis method to record any payments received on non-accrual assets. The Company resumes the accrual of interest on fixed maturity securities and loans that are currently making contractual payments or for those that are not current where the borrower has paid timely (less than 30 days outstanding). Credit Quality Indicators For TREs, the Company’s key credit quality indicator is loan-to-value (LTV). Given that TRE loans involve properties undergoing renovation or construction, loan-to-value provides the most insight into the credit risk of the loan. The Company monitors the performance of the loans periodically, but not less frequently than quarterly. For CMLs, the Company’s key credit quality indicators include LTV and debt service coverage ratios (DSCR). LTV is calculated by dividing the current outstanding loan balance by the most recent estimated property value. DSCR is the most recently available operating income of the underlying property compared to the required debt service of the loan. For MMLs and held-to-maturity fixed maturity securities, the Company’s key credit quality indicator is credit ratings. The Company’s held-to-maturity portfolio is composed of investment grade securities that are senior unsecured instruments, while its MMLs generally have below-investment-grade ratings but are typically senior secured instruments. The Company monitors the credit ratings periodically, but not less frequently than quarterly. For the Company’s reinsurance recoverable balance, the key credit quality indicator is the credit rating of the Company’s reinsurance counterparty. The Company uses external credit ratings focused on the reinsurer’s financial strength and credit worthiness. The Company's counterparties are rated A+. The Company monitors the credit ratings periodically, but not less frequently than quarterly. The following tables present as of March 31, 2020 the amortized cost basis of TREs, CMLs and MMLs by year of origination and credit quality indicator . Transitional Real Estate Loans (In millions) 2020 2019 2018 2017 2016 Prior Total Loan-to-Value Ratio: 0%-59.99% $ 33 $ 471 $ 409 $ 155 $ 20 $ 57 $ 1,145 60%-69.99% 190 777 834 436 0 0 2,237 70%-79.99% 81 858 997 250 14 0 2,200 80% or greater 25 36 0 0 0 0 61 Total $ 329 $ 2,142 $ 2,240 $ 841 $ 34 $ 57 $ 5,643 Commercial Mortgage Loans (In millions) 2020 2019 2018 2017 2016 Prior Total Weighted-Average DSCR Loan-to-Value Ratio: 0%-59.99% $ 12 $ 474 $ 156 $ 69 $ 683 $ 0 $ 1,394 2.43 60%-69.99% 27 190 16 0 90 0 323 1.74 70%-79.99% 0 0 0 0 23 0 23 1.32 Total 39 664 172 69 796 0 1,740 2.29 Weighted Average DSCR 1.84 2.33 2.16 2.37 2.30 0 2.29 Middle Market Loans (In millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Credit Ratings: BBB $ 9 $ 57 $ 52 $ 22 $ 12 $ 0 $ 15 $ 167 BB 86 277 187 140 56 20 84 850 B 210 827 466 309 98 58 338 2,306 CCC 0 58 10 34 25 4 15 146 CC 0 1 0 18 0 2 2 23 Total $ 305 $ 1,220 $ 715 $ 523 $ 191 $ 84 $ 454 $ 3,492 Allowance for Credit Losses The Company calculates its allowance for credit losses for held-to-maturity fixed maturity securities, loan receivables, loan commitments and reinsurance recoverable by grouping assets with similar risk characteristics when there is not a specific expectation of a loss for an individual asset. For held-to-maturity fixed maturity securities, MMLs, and MML commitments, the Company groups assets by credit ratings, industry, and country. The Company groups CMLs and TREs and respective loan commitments by property type, property location and the property’s loan-to-value and debt service coverage ratios. The credit allowance for the reinsurance recoverable balance is estimated using a probability-of-default (PD) / loss-given-default (LGD) method. The Company’s methodology for estimating credit losses for available-for-sale fixed maturity securities utilizes the discounted cash flow model, based on past events, current market conditions and future economic conditions, as well as industry analysis and credit ratings of the fixed maturity securities. In addition, the Company evaluates the specific issuer’s probability of default and expected recovery of its position in the event of default based on the underlying financial condition and assets of the borrower as well as seniority and/or security of other debt holders in the issuer when developing management’s best estimate of expected cash flows. The credit allowance for held-to-maturity fixed maturity securities and loan receivables is estimated using a PD / LGD method, discounted for the time value of money. For held-to-maturity fixed maturity securities, available-for-sale fixed maturity securities and loan receivables, the Company includes the change in present value due to the passage of time in the change in the allowance for credit losses. The Company’s methodology for estimating credit losses utilizes the contractual maturity date of the financial asset, adjusted when necessary to reflect the expected timing of repayment (such as prepayment options, renewal options, call options, or extension options). The Company applies reasonable and supportable forecasts of macroeconomic variables that impact the determination of PD/LGD over a two-year period for held-to-maturity fixed maturity securities and MMLs. The Company reverts to historical loss information over one year, following the two-year forecast period. For the CML and TRE portfolio, the Company applies reasonable and supportable forecasts of macroeconomic variables as well as national and local real-estate market factors to estimate future credit losses where the market factors revert back to historical levels over time with the period being dependent on current market conditions, projected market conditions and difference in the current and historical market levels for each factor. The Company continuously monitors the estimation methodology, due to changes in portfolio composition, changes in underwriting practices and significant events or conditions and makes adjustments as necessary. As of March 31, 2020 , and December 31, 2019 , the Company had no loans that were past due in regards to principal and/or interest payments. Additionally, the number of loans the Company held on nonaccrual status was immaterial as of March 31, 2020 , and December 31, 2019 . The Company had no troubled debt restructurings during the three months ended March 31, 2020 and 2019. The following table presents the roll forward of the allowance for credit losses by portfolio segment during the three-month period ended March 31, 2020 . (in millions) Transitional Real Estate Loans Commercial Mortgage Loans Middle Market Loans Held to Maturity Securities Available for Sale Securities Reinsurance Recoverables Balance at December 31, 2019 (1) $ (22 ) $ (3 ) $ (20 ) $ 0 $ 0 $ 0 Transition impact to retained earnings (2 ) (8 ) (33 ) (10 ) 0 (11 ) (Addition to) release of allowance for credit losses (3 ) 0 (34 ) 1 (63 ) 0 Balance at March 31, 2020 $ (27 ) $ (11 ) $ (87 ) $ (9 ) $ (63 ) $ (11 ) (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only. For assets that are subject to the credit loss measurement, the change in credit loss allowance will be significantly impacted by purchases and sales in those assets during the period as well as entering into new non-cancelable loan commitments. During the first quarter of 2020, the Company entered into a loan commitment with an external manager that met the requirements to recognize a credit loss on over $2.2 billion of loan commitments over the next few years. The estimate of credit losses for loan commitments as of March 31, 2020 was $60 million . Other Investments The table below reflects the composition of the carrying value for other investments as of the periods presented. (In millions) March 31, 2020 December 31, 2019 Other investments: Policy loans $ 253 $ 250 Short-term investments (1) 892 628 Limited partnerships 669 569 Other 29 30 Total other investments $ 1,843 $ 1,477 (1) Includes securities lending collateral As of March 31, 2020 , the Company had $1.4 billion in outstanding commitments to fund alternative investments in limited partnerships. Variable Interest Entities (VIEs) As a condition of its involvement or investment in a VIE, the Company enters into certain protective rights and covenants that preclude changes in the structure of the VIE that would alter the creditworthiness of the Company's investment or its beneficial interest in the VIE. For those VIEs other than certain unit trust structures, the Company's involvement is passive in nature. The Company has not, nor has it been, required to purchase any securities issued in the future by these VIEs. The Company's ownership interest in VIEs is limited to holding the obligations issued by them. The Company has no direct or contingent obligations to fund the limited activities of these VIEs, nor does it have any direct or indirect financial guarantees related to the limited activities of these VIEs. The Company has not provided any assistance or any other type of financing support to any of the VIEs it invests in, nor does it have any intention to do so in the future. For those VIEs in which the Company holds debt obligations, the weighted-average lives of the Company's notes are very similar to the underlying collateral held by these VIEs where applicable. The Company's risk of loss related to its interests in any of its VIEs is limited to the carrying value of the related investments held in the VIE. VIEs - Consolidated The following table presents the cost or amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported. Investments in Consolidated Variable Interest Entities March 31, 2020 December 31, 2019 (In millions) Amortized (1) Fair Amortized Fair Assets: Fixed maturity securities, available for sale $ 3,208 $ 3,786 $ 3,308 $ 4,312 Commercial mortgage and other loans 9,051 8,737 7,956 8,015 Other investments (2) 550 550 494 494 Other assets (3) 89 89 169 169 Total assets of consolidated VIEs $ 12,898 $ 13,162 $ 11,927 $ 12,990 Liabilities: Other liabilities (3) $ 235 $ 235 $ 126 $ 126 Total liabilities of consolidated VIEs $ 235 $ 235 $ 126 $ 126 (1) Net of allowance for credit losses (2) Consists entirely of alternative investments in limited partnerships (3) Consists entirely of derivatives The Company is substantively the only investor in the consolidated VIEs listed in the table above. As the sole investor in these VIEs, the Company has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and is therefore considered to be the primary beneficiary of the VIEs that it consolidates. The Company also participates in substantially all of the variability created by these VIEs. The activities of these VIEs are limited to holding invested assets and foreign currency swaps, as appropriate, and utilizing the cash flows from these securities to service its investment. Neither the Company nor any of its creditors are able to obtain the underlying collateral of the VIEs unless there is an event of default or other specified event. For those VIEs that contain a swap, the Company is not a direct counterparty to the swap contracts and has no control over them. The Company's loss exposure to these VIEs is limited to its original investment. The Company's consolidated VIEs do not rely on outside or ongoing sources of funding to support their activities beyond the underlying collateral and swap contracts, if applicable. With the exception of its investment in unit trust structures, the underlying collateral assets and funding of the Company's consolidated VIEs are generally static in nature. Investments in Unit Trust Structures The Company also utilizes unit trust structures in its Aflac Japan segment to invest in various asset classes. As the sole investor of these VIEs, the Company is required to consolidate these trusts under U.S. GAAP. VIEs - Not Consolidated The table below reflects the amortized cost, fair value and balance sheet caption in which the Company's investment in VIEs not consolidated are reported. Investments in Variable Interest Entities Not Consolidated March 31, 2020 December 31, 2019 (In millions) Amortized Fair Amortized Fair Assets: Fixed maturity securities, available for sale $ 5,999 $ 6,397 $ 4,129 $ 4,884 Fixed maturity securities, held to maturity 0 0 1,848 2,236 Other investments (1) 119 119 75 74 Total investments in VIEs not consolidated $ 6,118 $ 6,516 $ 6,052 $ 7,194 (1) Consists entirely of alternative investments in limited partnerships The Company holds alternative investments in limited partnerships that have been determined to be VIEs. These partnerships invest in private equity and structured investments. The Company’s maximum exposure to loss on these investments is limited to the amount of its investment. The Company is not the primary beneficiary of these VIEs and is therefore not required to consolidate them. The Company classifies these investments as Other investments in the consolidated balance sheets. Certain investments in VIEs that the Company is not required to consolidate are investments that are in the form of debt obligations from the VIEs that are irrevocably and unconditionally guaranteed by their corporate parents or sponsors. These VIEs are the primary financing vehicles used by their corporate sponsors to raise financing in the capital markets. The variable interests created by these VIEs are principally or solely a result of the debt instruments issued by them. The Company does not have the power to direct the activities that most significantly i

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS The Company's freestanding derivative financial instruments have historically consisted of: • foreign currency forwards and options used in hedging foreign exchange risk on U.S. dollar-denominated investments in Aflac Japan's portfolio • foreign currency forwards and options used to economically hedge certain portions of forecasted cash flows denominated in yen and hedge the Company's long term exposure to a weakening yen • cross-currency interest rate swaps, also referred to as foreign currency swaps, associated with certain senior notes and subordinated debentures • foreign currency swaps and, in prior periods, credit default swaps that are associated with investments in special-purpose entities, including VIEs where the Company is the primary beneficiary • interest rate swaps used to economically hedge interest rate fluctuations in certain variable-rate investments • interest rate swaptions used to hedge changes in the fair value associated with interest rate fluctuations for certain U.S. dollar-denominated available-for-sale fixed-maturity securities. Some of the Company's derivatives are designated as cash flow hedges, fair value hedges or net investment hedges; however, other derivatives do not qualify for hedge accounting or the Company elects not to designate them as accounting hedges. Derivative Types Foreign currency forwards and options are executed for the Aflac Japan segment in order to hedge the currency risk on the carrying value of certain U.S. dollar-denominated investments. The average maturity of these forwards and options can change depending on factors such as market conditions and types of investments being held. In situations where the maturity of the forwards and options is shorter than the underlying investment being hedged, the Company may enter into new forwards and options near maturity of the existing derivative in order to continue hedging the underlying investment. In forward transactions, Aflac Japan agrees with another party to buy a fixed amount of yen and sell a corresponding amount of U.S. dollars at a specified future date. Aflac Japan also executes foreign currency option transactions in a collar strategy, where Aflac Japan agrees with another party to simultaneously purchase put options and sell call options. In the purchased put transactions, Aflac Japan obtains the option to buy a fixed amount of yen and sell a corresponding amount of U.S. dollars at a specified future date. In the sold call transaction, Aflac Japan agrees to sell a fixed amount of yen and buy a corresponding amount of U.S. dollars at a specified future date. The combination of purchasing the put option and selling the call option results in no net premium being paid (i.e. a costless or zero-cost collar). Additionally, the Company enters into purchased options, acting as caps to protect the downside of the sold call options beyond a specified level. As opposed to the collar strategies which are fair value hedges, these sold call option caps are classified as non-qualifying hedges. From time to time, the Company may also enter into foreign currency forwards and options to hedge the currency risk associated with the net investment in Aflac Japan. In these forward transactions, Aflac agrees with another party to buy a fixed amount of U.S. dollars and sell a corresponding amount of yen at a specified price at a specified future date. In the option transactions, the Company may use a combination of foreign currency options to protect expected future cash flows by simultaneously purchasing yen put options (options that protect against a weakening yen) and selling yen call options (options that limit participation in a strengthening yen). The combination of these two actions create a zero-cost collar. Additionally, the Company enters into purchased options to hedge cash flows from the net investment in Aflac Japan. The Company enters into foreign currency swaps pursuant to which it exchanges an initial principal amount in one currency for an initial principal amount of another currency, with an agreement to re-exchange the principal amounts at a future date. There may also be periodic exchanges of payments at specified intervals based on the agreed upon rates and notional amounts. Foreign currency swaps are used primarily in the consolidated VIEs in the Company's Aflac Japan portfolio to convert foreign-denominated cash flows to yen, the functional currency of Aflac Japan, in order to minimize cash flow fluctuations. The Company also uses foreign currency swaps to economically convert certain of its U.S. dollar-denominated senior note and subordinated debenture principal and interest obligations into yen-denominated obligations. In order to reduce investment income volatility from its variable-rate investments, the Company enters into receive–fixed, pay–floating interest rate swaps. These derivatives are cleared and settled through a central clearinghouse. Swaptions are used to mitigate the adverse impact resulting from significant changes in the fair value of U.S. dollar-denominated available-for-sale securities due to fluctuation in interest rates. In a payer swaption, the Company pays a premium to obtain the right, but not the obligation, to enter into a swap contract where it will pay a fixed rate and receive a floating rate. Interest rate swaption collars are combinations of two swaption positions. In order to maximize the efficiency of the collars while minimizing cost, a collar strategy is used whereby the Company purchases a long payer swaption (the Company purchases an option that allows it to enter into a swap where the Company will pay the fixed rate and receive the floating rate of the swap) and sells a short receiver swaption (the Company sells an option that provides the counterparty with the right to enter into a swap where the Company will receive the fixed rate and pay the floating rate of the swap). The combination of purchasing the long payer swaption and selling the short receiver swaption results in no net premium being paid (i.e. a costless or zero-cost collar). Derivative Balance Sheet Classification The table below summarizes the balance sheet classification of the Company's derivative fair value amounts, as well as the gross asset and liability fair value amounts. The fair value amounts presented do not include income accruals. Derivative assets are included in “Other Assets,” while derivative liabilities are included in “Other Liabilities” within the Company’s Consolidated Balance Sheets. The notional amount of derivative contracts represents the basis upon which pay or receive amounts are calculated and are not reflective of exposure or credit risk. March 31, 2020 December 31, 2019 (In millions) Asset Liability Asset Liability Hedge Designation/ Derivative Notional Fair Value Fair Value Notional Fair Value Fair Value Cash flow hedges: Foreign currency swaps - VIE $ 75 $ 0 $ 11 $ 75 $ 0 $ 8 Total cash flow hedges 75 0 11 75 0 8 Fair value hedges: Foreign currency forwards 63 0 1 964 0 38 Foreign currency options 8,809 12 23 11,573 0 5 Interest rate swaptions 243 0 0 243 0 0 Total fair value hedges 9,115 12 24 12,780 0 43 Net investment hedge: Foreign currency forwards 4,985 85 6 4,952 72 2 Foreign currency options 2,040 7 0 2,000 0 0 Total net investment hedge 7,025 92 6 6,952 72 2 Non-qualifying strategies: Foreign currency swaps 2,250 66 38 2,800 72 78 Foreign currency swaps - VIE 2,587 89 224 2,587 169 118 Foreign currency forwards 20,614 184 420 19,821 166 337 Foreign currency options 9,248 8 0 9,553 0 0 Interest rate swaps 2,370 21 0 7,120 3 0 Interest rate swaptions 7 0 0 7 0 0 Total non-qualifying strategies 37,076 368 682 41,888 410 533 Total derivatives $ 53,291 $ 472 $ 723 $ 61,695 $ 482 $ 586 Cash Flow Hedges For certain variable-rate U.S. dollar-denominated available-for-sale securities held by Aflac Japan via consolidated VIEs, foreign currency swaps are used to swap the USD variable rate interest and principal payments to fixed rate JPY interest and principal payments. The Company has designated foreign currency swaps as a hedge of the variability in cash flows of a forecasted transaction or of amounts to be received or paid related to a recognized asset (“cash flow” hedge). The remaining maximum length of time for which these cash flows are hedged is approximately seven years. The derivatives in the Company's consolidated VIEs that are not designated as accounting hedges are discussed in the "non-qualifying strategies" section of this note. Fair Value Hedges The Company designates and accounts for certain foreign currency forwards, options, and interest rate swaptions as fair value hedges when they meet the requirements for hedge accounting. The Company recognizes gains and losses on these derivatives as well as the offsetting gain or loss on the related hedged items in current earnings. Foreign currency forwards and options hedge the foreign currency exposure of certain U.S. dollar-denominated available-for-sale fixed-maturity investments held in Aflac Japan. The change in the fair value of the foreign currency forwards related to the changes in the difference between the spot rate and the forward price is excluded from the assessment of hedge effectiveness. The change in fair value of the foreign currency option related to the time value of the option is recognized in current earnings and is excluded from the assessment of hedge effectiveness. Interest rate swaptions hedge the interest rate exposure of certain U.S. dollar-denominated available-for-sale securities held in Aflac Japan. For these hedging relationships, the Company excludes time value from the assessment of hedge effectiveness and recognizes changes in the intrinsic value of the swaptions in current earnings within net investment income. The change in the time value of the swaptions is recognized in other comprehensive income (loss) and amortized into earnings (net investment income) over its legal term. The following table presents the gains and losses on derivatives and the related hedged items in fair value hedges. Fair Value Hedging Relationships (In millions) Hedging Derivatives Hedged Items Hedging Derivatives Hedged Items Total Gains (Losses) (1) Gains (Losses) (2) Gains (Losses) (2) Net Investment Gains (Losses) Recognized for Fair Value Hedge Three Months Ended March 31, 2020: Foreign currency Fixed maturity securities $ (16 ) $ (7 ) $ (9 ) $ 10 $ 1 Total gains (losses) $ (16 ) $ (7 ) $ (9 ) $ 10 $ 1 Three Months Ended March 31, 2019: Foreign currency forwards Fixed maturity securities $ 9 $ (10 ) $ 19 $ (18 ) $ 1 Foreign currency options Fixed maturity securities (4 ) (4 ) 0 0 0 Interest rate Fixed maturity securities (1 ) (1 ) 0 0 0 Total gains (losses) $ 4 $ (15 ) $ 19 $ (18 ) $ 1 (1) Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss). (2) Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the three -month periods ended March 31, 2020 and 2019, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial. The following table shows the carrying amounts of assets designated and qualifying as hedged items in fair value hedges of interest rate risk and the related cumulative hedge adjustment included in the carrying amount. (In millions) Carrying Amount of the Hedged Assets/(Liabilities) (1) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities) March 31, 2020 December 31, 2019 March 31, 2020 December 31, 2019 Fixed maturity securities $ 4,469 $ 4,633 $ 249 $ 256 (1) The balance includes hedging adjustment on discontinued hedging relationships of $249 in 2020 and $256 in 2019. The total notional amount of the Company's interest rate swaptions was $243 in 2020 and $243 in 2019. The hedging adjustment related to these derivatives was immaterial. Net Investment Hedge The Company's investment in Aflac Japan is affected by changes in the yen/dollar exchange rate. To mitigate this exposure, the Parent Company's yen-denominated liabilities (see Note 8) have been designated as non-derivative hedges. Beginning in July 2019, certain foreign currency forwards and options were designated as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan. Prior to April 1, 2018, foreign currency forwards and options were also designated as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan. The Company's net investment hedge was effective during the three -month periods ended March 31, 2020 and 2019 , respectively. Non-qualifying Strategies For the Company's derivative instruments in consolidated VIEs that do not qualify for hedge accounting treatment, all changes in their fair value are reported in current period earnings within n et i nvestment gains (losses). The amount of gain or loss recognized in earnings for the Company's VIEs is attributable to the derivatives in those investment structures. While the change in value of the swaps is recorded through current period earnings, the change in value of the available-for-sale fixed maturity securities associated with these swaps is recorded through other comprehensive income. As of March 31, 2020 , the Parent Company had $2.3 billion notional amount of cross-currency interest rate swap agreements related to certain of its U.S. dollar-denominated senior notes to effectively convert a portion of the interest on the notes from U.S dollar to Japanese yen. Changes in the values of these swaps are recorded through current period earnings. For additional information regarding these swaps, see Note 9 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report. The Company uses foreign exchange forwards and options to economically mitigate the currency risk of some of its U.S. dollar-denominated loan receivables held within the Aflac Japan segment. These arrangements are not designated as accounting hedges, as the foreign currency remeasurement of the loan receivables impacts current period earnings, and generally offsets gains and losses from foreign exchange forwards within net investment gains (losses). The Company also has certain foreign exchange forwards on U.S. dollar-denominated available-for-sale securities where hedge accounting is not being applied. Prior to July 2019, in order to economically mitigate currency risk of future yen dividends from Aflac Japan while lowering consolidated hedge costs associated with Aflac Japan's U.S. dollar investment hedging, the Parent Company entered into offsetting hedge positions using foreign exchange forwards. This activity is reported in the Corporate and other segment. As of July 1, 2019, the Parent Company designates these foreign exchange forward contracts as accounting hedges of its net investment in Aflac Japan. The Company uses interest rate swaps to economically convert the variable rate investment income to a fixed rate on certain variable-rate investments. Impact of Derivatives and Hedging Instruments The following table summarizes the impact to net investment gains (losses) and other comprehensive income (loss) from all derivatives and hedging instruments. Three Months Ended March 31, 2020 2019 (In millions) Net Investment Income (1) Net Investment Other (2) Net Investment Income (1) Net Investment Other (2) Qualifying hedges: Cash flow hedges: Foreign currency swaps - VIE $ (1 ) $ 0 $ (4 ) $ (1 ) $ 0 $ (2 ) Total cash flow hedges (1 ) 0 (3 ) (4 ) (1 ) 0 (3 ) (2 ) Fair value hedges: Foreign currency forwards (3) (6 ) (9 ) Foreign currency options (3) 0 (4 ) Interest rate swaptions (3) 0 0 0 0 0 (1 ) Total fair value hedges 0 (6 ) 0 0 (13 ) (1 ) Net investment hedge: Non-derivative hedging instruments 0 6 0 0 Foreign currency forwards 51 (25 ) 0 0 Foreign currency options 6 0 0 0 Total net investment hedge 57 (19 ) 0 0 Non-qualifying strategies: Foreign currency swaps 50 44 Foreign currency swaps - VIE (195 ) (16 ) Foreign currency forwards (36 ) (21 ) Foreign currency options (2 ) 0 Interest rate swaps 47 6 Total non-qualifying strategies (136 ) 13 Total $ (1 ) $ (85 ) $ (23 ) $ (1 ) $ 0 $ (3 ) (1) Cash flow hedge items and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses) on derivatives and net investment hedge items are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss). (2) Impact of cash flow hedges reported as net investment gains (losses) includes an immaterial amount of gains or losses reclassified from accumulated other comprehensive income (loss) into earnings. It also includes an immaterial amount excluded from effectiveness testing during the three -month periods ended March 31, 2020 and 2019 , respectively. (3) Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail) As of March 31, 2020 , deferred gains and losses on derivative instruments recorded in accumulated other comprehensive income that are expected to be reclassified to earnings during the next twelve months were immaterial. Credit Risk Assumed through Derivatives For the foreign currency and credit default swaps associated with the Company's VIE investments for which it is the primary beneficiary, the Company bears the risk of loss due to counterparty default even though it is not a direct counterparty to those contracts. The Company is a direct counterparty to the foreign currency swaps that it has entered into in connection with certain of its senior notes and subordinated debentures; foreign currency forwards; and foreign currency options, and therefore the Company is exposed to credit risk in the event of nonperformance by the counterparties in those contracts. The risk of counterparty default for the Company's foreign currency swaps, certain foreign currency forwards, and foreign currency options is mitigated by collateral posting requirements that counterparties to those transactions must meet. As of March 31, 2020 , all of the Company's derivative agreement counterparties were investment grade. The Company engages in over-the-counter (OTC) bilateral derivative transactions directly with unaffiliated third parties under International Swaps and Derivatives Association, Inc. (ISDA) agreements and other documentation. Most of the ISDA agreements also include Credit Support Annexes (CSAs) provisions, which generally provide for two-way collateral postings at the first dollar of exposure. The Company mitigates the risk that counterparties to transactions might be unable to fulfill their contractual obligations by monitoring counterparty credit exposure and collateral value while generally requiring that collateral be posted at the outset of the transaction. In addition, a significant portion of the derivative transactions have provisions that give the counterparty the right to terminate the transaction upon a downgrade of Aflac’s financial strength rating. The actual amount of payments that the Company could be required to make depends on market conditions, the fair value of outstanding affected transactions, and other factors prevailing at and after the time of the downgrade. The Company also engages in OTC cleared derivative transactions through regulated central clearing counterparties. These positions are marked to market and margined on a daily basis (both initial margin and variation margin), and the Company has minimal exposure to credit-related losses in the event of nonperformance by counterparties to these derivatives. Collateral posted by the Company to third parties for derivative transactions can generally be repledged or resold by the counterparties. The aggregate fair value of all derivative instruments with credit-risk-related contingent features that were in a net liability position by counterparty was approximately $348 million and $301 million as of March 31, 2020 , and December 31, 2019 , respectively. If the credit-risk-related contingent features underlying these agreements had been triggered on March 31, 2020 , the Company estimates that it would be required to post a maximum of $171 million of additional collateral to these derivative counterparties. The Company is generally allowed to sell or repledge collateral obtained from its derivative counterparties, although it does not typically exercise such rights. (See the Offsetting tables below for collateral posted or received as of the reported balance sheet dates.) Offsetting of Financial Instruments and Derivatives Most of the Company's derivative instruments are subject to enforceable master netting arrangements that provide for the net settlement of all derivative contracts between the Parent Company or its subsidiaries and the respective counterparty in the event of default or upon the occurrence of certain termination events. Collateral support agreements with the master netting arrangements generally provide that the Company will receive or pledge financial collateral at the first dollar of exposure. The Company has securities lending agreements with unaffiliated financial institutions that post collateral to the Company in return for the use of its fixed maturity and public equity securities (see Note 3). When the Company has entered into securities lending agreements with the same counterparty, the agreements generally provide for net settlement in the event of default by the counterparty. This right of set-off allows the Company to keep and apply collateral received if the counterparty failed to return the securities borrowed from the Company as contractually agreed. The tables below summarize the Company's derivatives and securities lending transactions, and as reflected in the tables, in accordance with U.S. GAAP, the Company's policy is to not offset these financial instruments in the Consolidated Balance Sheets. Offsetting of Financial Assets and Derivative Assets March 31, 2020 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Assets Gross Amount Offset in Balance Sheet Net Amount of Assets Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Received Net Amount Derivative assets: Derivative assets subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 362 $ 0 $ 362 $ (229 ) $ (7 ) $ (121 ) $ 5 OTC - cleared 21 0 21 0 0 (11 ) 10 Total derivative assets subject to a master netting agreement or offsetting arrangement 383 0 383 (229 ) (7 ) (132 ) 15 Derivative assets not subject to a master netting agreement or offsetting arrangement OTC - bilateral 89 89 89 Total derivative assets not subject to a master netting agreement or offsetting arrangement 89 89 89 Total derivative assets 472 0 472 (229 ) (7 ) (132 ) 104 Securities lending and similar arrangements 2,952 0 2,952 0 0 (2,952 ) 0 Total $ 3,424 $ 0 $ 3,424 $ (229 ) $ (7 ) $ (3,084 ) $ 104 December 31, 2019 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Assets Gross Amount Offset in Balance Sheet Net Amount of Assets Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Received Net Amount Derivative assets: Derivative assets subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 310 $ 0 $ 310 $ (190 ) $ (7 ) $ (113 ) $ 0 OTC - cleared 3 0 3 0 0 0 3 Total derivative assets subject to a master netting agreement or offsetting arrangement 313 0 313 (190 ) (7 ) (113 ) 3 Derivative assets not subject to a master netting agreement or offsetting arrangement OTC - bilateral 169 169 169 Total derivative assets not subject to a master netting agreement or offsetting arrangement 169 169 169 Total derivative assets 482 0 482 (190 ) (7 ) (113 ) 172 Securities lending and similar arrangements 1,860 0 1,860 0 0 (1,860 ) 0 Total $ 2,342 $ 0 $ 2,342 $ (190 ) $ (7 ) $ (1,973 ) $ 172 Offsetting of Financial Liabilities and Derivative Liabilities March 31, 2020 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Liabilities Gross Amount Offset in Balance Sheet Net Amount of Liabilities Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Pledged Net Amount Derivative liabilities: Derivative liabilities subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 488 $ 0 $ 488 $ (229 ) $ (175 ) $ (2 ) $ 82 Total derivative liabilities subject to a master netting agreement or offsetting arrangement 488 0 488 (229 ) (175 ) (2 ) 82 Derivative liabilities not subject to a master netting agreement or offsetting arrangement OTC - bilateral 235 235 235 Total derivative liabilities not subject to a master netting agreement or offsetting arrangement 235 235 235 Total derivative liabilities 723 0 723 (229 ) (175 ) (2 ) 317 Securities lending and similar arrangements 2,969 0 2,969 (2,952 ) 0 0 17 Total $ 3,692 $ 0 $ 3,692 $ (3,181 ) $ (175 ) $ (2 ) $ 334 December 31, 2019 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Liabilities Gross Amount Offset in Balance Sheet Net Amount of Liabilities Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Pledged Net Amount Derivative liabilities: Derivative liabilities subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 459 $ 0 $ 459 $ (190 ) $ (222 ) $ (32 ) $ 15 OTC - cleared 1 0 1 0 0 (1 ) 0 Total derivative liabilities subject to a master netting agreement or offsetting arrangement 460 0 460 (190 ) (222 ) (33 ) 15 Derivative liabilities not subject to a master netting agreement or offsetting arrangement OTC - bilateral 126 126 126 Total derivative liabilities not subject to a master netting agreement or offsetting arrangement 126 126 126 Total derivative liabilities 586 0 586 (190 ) (222 ) (33 ) 141 Securities lending and similar arrangements 1,876 0 1,876 (1,860 ) 0 0 16 Total $ 2,462 $ 0 $ 2,462 $ (2,050 ) $ (222 ) $ (33 ) $ 157 For additional information on the Company's financial instruments, see the accompanying Notes 1, 3 and 5 and Notes 1, 3 and 5 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Fair Value Hierarchy U.S. GAAP specifies a hierarchy of valuation techniques based on whether the inputs to those valuation techniques are observable or unobservable. These two types of inputs create three valuation hierarchy levels. Level 1 valuations reflect quoted market prices for identical assets or liabilities in active markets. Level 2 valuations reflect quoted market prices for similar assets or liabilities in an active market, quoted market prices for identical or similar assets or liabilities in non-active markets or model-derived valuations in which all significant valuation inputs are observable in active markets. Level 3 valuations reflect valuations in which one or more of the significant inputs are not observable in an active market. The following tables present the fair value hierarchy levels of the Company's assets and liabilities that are measured and carried at fair value on a recurring basis. March 31, 2020 (In millions) Quoted Prices in Significant Significant Total Assets: Securities available for sale, carried at Fixed maturity securities: Government and agencies $ 35,469 $ 1,509 $ 0 $ 36,978 Municipalities 0 2,440 0 2,440 Mortgage- and asset-backed securities 0 309 188 497 Public utilities 0 8,894 298 9,192 Sovereign and supranational 0 1,609 0 1,609 Banks/financial institutions 0 10,355 23 10,378 Other corporate 0 34,949 245 35,194 Total fixed maturity securities 35,469 60,065 754 96,288 Equity securities 509 69 82 660 Other investments 892 0 0 892 Cash and cash equivalents 4,148 0 0 4,148 Other assets: Foreign currency swaps 0 66 89 155 Foreign currency forwards 0 269 0 269 Foreign currency options 0 27 0 27 Interest rate swaps 0 21 0 21 Total other assets 0 383 89 472 Total assets $ 41,018 $ 60,517 $ 925 $ 102,460 Liabilities: Other liabilities: Foreign currency swaps $ 0 $ 38 $ 235 $ 273 Foreign currency forwards 0 427 0 427 Foreign currency options 0 23 0 23 Total liabilities $ 0 $ 488 $ 235 $ 723 December 31, 2019 (In millions) Quoted Prices in Significant Significant Total Assets: Securities available for sale, carried at Fixed maturity securities: Government and agencies $ 34,878 $ 1,522 $ 0 $ 36,400 Municipalities 0 1,847 0 1,847 Mortgage- and asset-backed securities 0 232 178 410 Public utilities 0 6,556 224 6,780 Sovereign and supranational 0 1,042 0 1,042 Banks/financial institutions 0 10,264 23 10,287 Other corporate 0 34,234 262 34,496 Total fixed maturity securities 34,878 55,697 687 91,262 Equity securities 642 80 80 802 Other investments 628 0 0 628 Cash and cash equivalents 4,896 0 0 4,896 Other assets: Foreign currency swaps 0 72 169 241 Foreign currency forwards 0 238 0 238 Interest rate swaps 0 3 0 3 Total other assets 0 313 169 482 Total assets $ 41,044 $ 56,090 $ 936 $ 98,070 Liabilities: Other liabilities: Foreign currency swaps $ 0 $ 78 $ 126 $ 204 Foreign currency forwards 0 377 0 377 Foreign currency options 0 5 0 5 Total liabilities $ 0 $ 460 $ 126 $ 586 The following tables present the carrying amount and fair value categorized by fair value hierarchy level for the Company's financial instruments that are not carried at fair value. March 31, 2020 (In millions) Carrying Quoted Prices in Significant Significant Total Assets: Securities held to maturity, Fixed maturity securities: Government and agencies $ 22,384 $ 27,842 $ 352 $ 0 $ 28,194 Municipalities 362 0 484 0 484 Public utilities 45 0 59 0 59 Sovereign and 464 0 578 0 578 Other corporate 23 0 32 0 32 Commercial mortgage and 10,750 0 0 10,390 10,390 Other investments (1) 29 0 29 0 29 Total assets $ 34,057 $ 27,842 $ 1,534 $ 10,390 $ 39,766 Liabilities: Other policyholders’ funds $ 7,422 $ 0 $ 0 $ 7,338 $ 7,338 Notes payable 6,597 0 6,607 274 6,881 Total liabilities $ 14,019 $ 0 $ 6,607 $ 7,612 $ 14,219 (1) Excludes policy loans of $253 and equity method investments of $669 , at carrying value December 31, 2019 (In millions) Carrying Quoted Prices in Significant Significant Total Assets: Securities held to maturity, Fixed maturity securities: Government and agencies $ 22,241 $ 27,937 $ 354 $ 0 $ 28,291 Municipalities 821 0 1,083 0 1,083 Mortgage and asset-backed 16 0 7 10 17 Public utilities 2,535 0 2,954 0 2,954 Sovereign and 1,123 0 1,320 0 1,320 Banks/financial institutions 916 0 1,018 0 1,018 Other corporate 2,433 0 2,911 0 2,911 Commercial mortgage and 9,569 0 0 9,648 9,648 Other investments (1) 30 0 30 0 30 Total assets $ 39,684 $ 27,937 $ 9,677 $ 9,658 $ 47,272 Liabilities: Other policyholders’ funds $ 7,317 $ 0 $ 0 $ 7,234 $ 7,234 Notes payable 6,408 0 6,663 272 6,935 Total liabilities $ 13,725 $ 0 $ 6,663 $ 7,506 $ 14,169 (1) Excludes policy loans of $250 and equity method investments of $569 , at carrying value Fair Value of Financial Instruments Fixed maturity and equity securities The Company determines the fair values of fixed maturity securities and public and privately-issued equity securities using the following approaches or techniques: price quotes and valuations from third party pricing vendors (including quoted market prices readily available from public exchange markets) and non-binding price quotes the Company obtains from outside brokers. A third party pricing vendor has developed valuation models to determine fair values of privately issued securities to reflect the impact of the persistent economic environment and the changing regulatory framework. These models are discounted cash flow (DCF) valuation models, but also use information from related markets, specifically the credit default swap (CDS) market to estimate expected cash flows. These models take into consideration any unique characteristics of the securities and make various adjustments to arrive at an appropriate issuer-specific loss adjusted credit curve. This credit curve is then used with the relevant recovery rates to estimate expected cash flows and modeling of additional features, including illiquidity adjustments, if necessary, to price the security by discounting those loss adjusted cash flows. In cases where a credit curve cannot be developed from the specific security features, the valuation methodology takes into consideration other market observable inputs, including: 1) the most appropriate comparable security(ies) of the issuer 2) issuer-specific CDS spreads 3) bonds or CDS spreads of comparable issuers with similar characteristics such as rating, geography, or sector 4) bond indices that are comparative in rating, industry, maturity and region. The pricing data and market quotes the Company obtains from outside sources, including third party pricing services, are reviewed internally for reasonableness. If a fair value appears unreasonable, the Company will re-examine the inputs and assess the reasonableness of the pricing data with the vendor. Additionally, the Company may compare the inputs to relevant market indices and other performance measurements. Based on management's analysis, the valuation is confirmed or may be revised if there is evidence of a more appropriate estimate of fair value based on available market data. The Company has performed verification of the inputs and calculations in any valuation models to confirm that the valuations represent reasonable estimates of fair value. For the periods presented, the Company has not adjusted the quotes or prices it obtains from the pricing services and brokers it uses. The following tables present the pricing sources for the fair values of the Company's fixed maturity and equity securities. March 31, 2020 (In millions) Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Total Securities available for sale, carried at fair value: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 35,469 $ 1,509 $ 0 $ 36,978 Total government and agencies 35,469 1,509 0 36,978 Municipalities: Third party pricing vendor 0 2,440 0 2,440 Total municipalities 0 2,440 0 2,440 Mortgage- and asset-backed securities: Third party pricing vendor 0 309 0 309 Broker/other 0 0 188 188 Total mortgage- and asset-backed securities 0 309 188 497 Public utilities: Third party pricing vendor 0 8,894 0 8,894 Broker/other 0 0 298 298 Total public utilities 0 8,894 298 9,192 Sovereign and supranational: Third party pricing vendor 0 1,609 0 1,609 Total sovereign and supranational 0 1,609 0 1,609 Banks/financial institutions: Third party pricing vendor 0 10,355 0 10,355 Broker/other 0 0 23 23 Total banks/financial institutions 0 10,355 23 10,378 Other corporate: Third party pricing vendor 0 34,949 0 34,949 Broker/other 0 0 245 245 Total other corporate 0 34,949 245 35,194 Total securities available for sale $ 35,469 $ 60,065 $ 754 $ 96,288 Equity securities, carried at fair value: Third party pricing vendor $ 509 $ 69 $ 0 $ 578 Broker/other 0 0 82 82 Total equity securities $ 509 $ 69 $ 82 $ 660 March 31, 2020 (In millions) Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Total Securities held to maturity, carried at amortized cost: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 27,842 $ 352 $ 0 $ 28,194 Total government and agencies 27,842 352 0 28,194 Municipalities: Third party pricing vendor 0 484 0 484 Total municipalities 0 484 0 484 Public utilities: Third party pricing vendor 0 59 0 59 Total public utilities 0 59 0 59 Sovereign and supranational: Third party pricing vendor 0 578 0 578 Total sovereign and supranational 0 578 0 578 Other corporate: Third party pricing vendor 0 32 0 32 Total other corporate 0 32 0 32 Total securities held to maturity $ 27,842 $ 1,505 $ 0 $ 29,347 December 31, 2019 (In millions) Quoted Prices in Active Markets Significant Observable Significant Unobservable Inputs Total Securities available for sale, carried at fair value: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 34,878 $ 1,522 $ 0 $ 36,400 Total government and agencies 34,878 1,522 0 36,400 Municipalities: Third party pricing vendor 0 1,847 0 1,847 Total municipalities 0 1,847 0 1,847 Mortgage- and asset-backed securities: Third party pricing vendor 0 232 0 232 Broker/other 0 0 178 178 Total mortgage- and asset-backed securities 0 232 178 410 Public utilities: Third party pricing vendor 0 6,556 0 6,556 Broker/other 0 0 224 224 Total public utilities 0 6,556 224 6,780 Sovereign and supranational: Third party pricing vendor 0 1,042 0 1,042 Total sovereign and supranational 0 1,042 0 1,042 Banks/financial institutions: Third party pricing vendor 0 10,264 0 10,264 Broker/other 0 0 23 23 Total banks/financial institutions 0 10,264 23 10,287 Other corporate: Third party pricing vendor 0 34,234 0 34,234 Broker/other 0 0 262 262 Total other corporate 0 34,234 262 34,496 Total securities available for sale $ 34,878 $ 55,697 $ 687 $ 91,262 Equity securities, carried at fair value: Third party pricing vendor $ 642 $ 80 $ 0 $ 722 Broker/other 0 0 80 80 Total equity securities $ 642 $ 80 $ 80 $ 802 December 31, 2019 (In millions) Quoted Prices in Active Markets Significant Observable Significant Unobservable Inputs Total Securities held to maturity, carried at amortized cost: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 27,937 $ 354 $ 0 $ 28,291 Total government and agencies 27,937 354 0 28,291 Municipalities: Third party pricing vendor 0 1,083 0 1,083 Total municipalities 0 1,083 0 1,083 Mortgage- and asset-backed securities: Third party pricing vendor 0 7 0 7 Broker/other 0 0 10 10 Total mortgage- and asset-backed securities 0 7 10 17 Public utilities: Third party pricing vendor 0 2,954 0 2,954 Total public utilities 0 2,954 0 2,954 Sovereign and supranational: Third party pricing vendor 0 1,320 0 1,320 Total sovereign and supranational 0 1,320 0 1,320 Banks/financial institutions: Third party pricing vendor 0 1,018 0 1,018 Total banks/financial institutions 0 1,018 0 1,018 Other corporate: Third party pricing vendor 0 2,911 0 2,911 Total other corporate 0 2,911 0 2,911 Total securities held to maturity $ 27,937 $ 9,647 $ 10 $ 37,594 The following is a discussion of the determination of fair value of the Company's remaining financial instruments. Derivatives The Company uses derivative instruments to manage the risk associated with certain assets. However, the derivative instrument may not be classified in the same fair value hierarchy level as the associated asset. Inputs used to value derivatives include, but are not limited to, interest rates, credit spreads, foreign currency forward and spot rates, and interest volatility. The significant inputs to pricing derivatives are generally observable in the market or can be derived by observable market data. When these inputs are observable, the derivatives are classified as Level 2. The fair value of foreign currency forward and options are based on observable market inputs, therefore they are classified as Level 2. To determine the fair value of its interest rate derivatives, the Company uses inputs that are generally observable in the market or can be derived from observable market data. Interest rate swaps are cleared trades. In a cleared swap contract, the clearinghouse provides benefits to the counterparties similar to contracts listed for investment traded on an exchange since it maintains a daily margin to mitigate counterparties' credit risk. These derivatives are priced using observable inputs, accordingly, they are classified as Level 2. For its interest rate swaptions, the Company estimates their fair values using observable market data, including interest rate curves and volatilities. Their fair values are also classified as Level 2. For derivatives associated with VIEs where the Company is the primary beneficiary, the Company is not the direct counterparty to the swap contracts. As a result, the fair value measurements incorporate the credit risk of the collateral associated with the VIE. Based on an analysis of these derivatives and a review of the methodology employed by the pricing vendor, the Company determined that due to the long duration of these swaps and the need to extrapolate from short-term observable data to derive and measure long-term inputs, certain inputs, assumptions and judgments are required to value future cash flows that cannot be corroborated by current inputs or current observable market data. As a result, the derivatives associated with the Company's consolidated VIEs are classified as Level 3 of the fair value hierarchy. Commercial mortgage and other loans Commercial mortgage and other loans include transitional real estate loans, commercial mortgage loans and middle market loans. The Company's loan receivables do not have readily determinable market prices and generally lack market liquidity. Fair values for loan receivables are determined based on the present value of expected future cash flows discounted at the applicable U.S. Treasury or London Interbank Offered Rate (LIBOR) yield plus an appropriate spread that considers other risk factors, such as credit and liquidity risk. The spreads are a significant component of the pricing inputs and are generally considered unobservable. Therefore, these investments have been assigned a Level 3 within the fair value hierarchy. Other investments Other investments includes short-term investments that are measured at fair value where amortized cost approximates fair value. Other policyholders' funds The largest component of the other policyholders' funds liability is the Company's annuity line of business in Aflac Japan. The Company's annuities have fixed benefits and premiums. For this product, the Company estimates the fair value to be equal to the cash surrender value. This is analogous to the value paid to policyholders on the valuation date if they were to surrender their policy. The Company periodically checks the cash value against discounted cash flow projections for reasonableness. The Company considers its inputs for this valuation to be unobservable and have accordingly classified this valuation as Level 3. Notes payable The fair values of the Company's publicly issued notes payable are determined by utilizing available sources of observable inputs from third party pricing vendors and are classified as Level 2. The fair values of the Company's yen-denominated loans approximate their carrying values and are classified as Level 3. Transfers between Hierarchy Levels and Level 3 Rollforward The following tables present the changes in fair value of the Company's investments and derivatives carried at fair value classified as Level 3. Three Months Ended Fixed Maturity Securities Equity Derivatives (1) (In millions) Mortgage- Public Banks/ Other Foreign Credit Total Balance, beginning of period $ 178 $ 224 $ 23 $ 262 $ 80 $ 43 $ 0 $ 810 Net investment gains (losses) included 0 0 0 0 0 (185 ) 0 (185 ) Unrealized gains (losses) included in other 1 (8 ) 0 (17 ) 0 (4 ) 0 (28 ) Purchases, issuances, sales and settlements: Purchases 0 83 0 0 2 0 0 85 Issuances 0 0 0 0 0 0 0 0 Sales 0 0 0 0 0 0 0 0 Settlements 0 (1 ) 0 0 0 0 0 (1 ) Transfers into Level 3 9 (2) 0 0 0 0 0 0 9 Transfers out of Level 3 0 0 0 0 0 0 0 0 Balance, end of period $ 188 $ 298 $ 23 $ 245 $ 82 $ (146 ) $ 0 $ 690 Changes in unrealized gains (losses) relating $ 0 $ 0 $ 0 $ 0 $ 0 $ (185 ) $ 0 $ (185 ) (1) Derivative assets and liabilities are presented net (2) Transfer due to reclassification of level 3 securities from HTM to AFS Three Months Ended Fixed Maturity Securities Equity Derivatives (1) (In millions) Mortgage- Public Banks/ Other Foreign Credit Total Balance, beginning of period $ 177 $ 109 $ 23 $ 213 $ 46 $ 80 $ 0 $ 648 Net investment gains (losses) included in earnings 0 0 0 0 0 (8 ) 0 (8 ) Unrealized gains (losses) included in other comprehensive income (loss) 1 1 0 1 0 (2 ) 0 1 Purchases, issuances, sales and settlements: Purchases 0 0 0 63 0 0 0 63 Issuances 0 0 0 0 0 0 0 0 Sales 0 0 0 (2 ) 0 0 0 (2 ) Settlements 0 0 0 0 0 0 0 0 Transfers into Level 3 0 0 0 25 (2) 0 0 0 25 Transfers out of Level 3 0 (25 ) (2) 0 (16 ) (3) 0 0 0 (41 ) Balance, end of period $ 178 $ 85 $ 23 $ 284 $ 46 $ 70 $ 0 $ 686 Changes in unrealized gains (losses) relating $ 0 $ 0 $ 0 $ 0 $ 0 $ (8 ) $ 0 $ (8 ) (1) Derivative assets and liabilities are presented net (2) Transfer due to sector classification change (3) Transfer due to availability of observable market inputs Fair Value Sensitivity Level 3 Significant Unobservable Input Sensitivity The following tables summarize the significant unobservable inputs used in the valuation of the Company's Level 3 investments and derivatives carried at fair value. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments. March 31, 2020 (In millions) Fair Value Valuation Technique(s) Unobservable Input Range Assets: Securities available for sale, carried at fair value: Fixed maturity securities: Mortgage- and asset-backed securities $ 188 Consensus pricing Offered quotes N/A (a) Public utilities 298 Discounted cash flow Credit spreads N/A (a) Banks/financial institutions 23 Consensus pricing Offered quotes N/A (a) Other corporate 245 Discounted cash flow Credit spreads N/A (a) Equity securities 82 Net asset value Offered quotes N/A (a) Other assets: Foreign currency swaps 15 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) CDS spreads 31 - 173 bps 74 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) Total assets $ 925 Liabilities: Other liabilities: Foreign currency swaps $ 224 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) CDS spreads 31 - 173 bps 11 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) Total liabilities $ 235 (a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs. (b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps (c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps December 31, 2019 (In millions) Fair Value Valuation Technique(s) Unobservable Input Range Assets: Securities available for sale, carried at fair value: Fixed maturity securities: Mortgage- and asset-backed securities $ 178 Consensus pricing Offered quotes N/A (a) Public utilities 224 Discounted cash flow Credit spreads N/A (a) Banks/financial institutions 23 Consensus pricing Offered quotes N/A (a) Other corporate 262 Discounted cash flow Credit spreads N/A (a) Equity securities 80 Net asset value Offered quotes N/A (a) Other assets: Foreign currency swaps 106 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) CDS spreads 10 - 100 bps 63 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) Total assets $ 936 Liabilities: Other liabilities: Foreign currency swaps $ 118 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) CDS spreads 13 - 159 bps 8 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) Total liabilities $ 126 (a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs. (b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps (c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps The following is a discussion of the significant unobservable inputs or valuation techniques used in determining the fair value of securities and derivatives classified as Level 3. Net Asset Value The Company holds certain unlisted equity securities whose fair value is derived based on the financial statements published by the investee. These securities do not trade on an active market and the valuations derived are dependent on the availability of timely financial reporting of the investee. Net asset value is an unobservable input in the determination of fair value of equity securities. Offered Quotes In circumstances where the Company's valuation model price is overridden because it implies a value that is not consistent with current market conditions, the Company will solicit bids from a limited number of brokers. The Company also receives unadjusted prices from brokers for its mortgage and asset-backed securities. These quotes are non-binding but are reflective of valuation best estimates at that particular point in time. Offered quotes are an unobservable input in the determination of fair value of mortgage- and asset-backed securities, certain banks/financial institutions, certain other corporate, and equity securities investments. Interest Rates and CDS Spreads The significant drivers of the valuation of the foreign exchange swaps are interest rates and CDS spreads. Some of the Company's swaps have long maturities that increase the sensitivity of the swaps to interest rate fluctuations. For the Company's foreign exchange or cross currency swaps that are in a net asset position, an increase in yen interest rates (all other factors held constant) will decrease the present value of the yen final settlement receivable (receive leg), thus decreasing the value of the swap as long as the derivative remains in a net asset position. Foreign exchange swaps also have a lump-sum final settlement of foreign exchange principal amounts at the termination of the swap. Assuming all other factors are held constant, an increase in yen interest rates will decrease the receive leg and decrease the net value of the swap. Likewise, holding all other factors constant, an increase in U.S. dollar interest rates will increase the swap's net value due to the decrease in the present value of the dollar final settlement payable (pay leg). The extinguisher feature in most of the Company's VIE swaps results in a cessation of cash flows and no further payments between the parties to the swap in the event of a default on the referenced or underlying collateral. To price this feature, the Company applies the survival probability of the referenced entity to the projected cash flows. The survival probability uses the CDS spreads and recovery rates to adjust the present value of the cash flows. For extinguisher swaps with positive values, an increase in CDS spreads decreases the likelihood of receiving the final exchange payments and reduces the value of the swap. For additional information on the Company's investments and financial instruments, see the accompanying Notes 1, 3 and 4 and Notes 1, 3 and 4 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report.

POLICY LIABILITIES

POLICY LIABILITIES	3 Months Ended
	Mar. 31, 2020
Insurance Loss Reserves [Abstract]
POLICY LIABILITIES	POLICY LIABILITIES Changes in the liability for unpaid policy claims were as follows: Three Months Ended (In millions) 2020 2019 Unpaid supplemental health claims, beginning of period $ 3,968 $ 3,952 Less reinsurance recoverables 31 29 Net balance, beginning of period 3,937 3,923 Add claims incurred during the period related to: Current year 1,837 1,825 Prior years (136 ) (167 ) Total incurred 1,701 1,658 Less claims paid during the period on claims incurred during: Current year 556 506 Prior years 1,144 1,137 Total paid 1,700 1,643 Effect of foreign exchange rate changes on unpaid claims 12 0 Net balance, end of period 3,950 3,938 Add reinsurance recoverables 33 29 Unpaid supplemental health claims, end of period 3,983 3,967 Unpaid life claims, end of period 710 658 Total liability for unpaid policy claims $ 4,693 $ 4,625 The incurred claims development related to prior years reflects favorable claims experience compared to previous estimates. The favorable claims development of $136 million for the three -month period ended March 31, 2020 comprises approximately $91 million from Japan, which represents approximately 67% of the total. Excluding the impact of foreign exchange of a gain of approximately $1 million from December 31, 2019 to March 31, 2020 , the favorable claims development in Japan would have been approximately $90 million , representing approximately 66% of the total. The Company has experienced continued favorable claim trends in 2020 for its core health products in Japan. The Company's experience in Japan related to the average length of stay in the hospital for cancer treatment has shown continued decline in the current period. In addition, cancer treatment patterns in Japan are continuing to be influenced by significant advances in early-detection techniques and by the increased use of pathological diagnosis rather than clinical exams. Additionally, follow-up radiation and chemotherapy treatments are occurring more often on an outpatient basis. Such changes in treatment not only increase the quality of life and initial outcomes for the patients, but also decrease the average length of each hospital stay, resulting in favorable claims development. The remainder of the favorable claims development related to prior years for the three -month period ended March 31, 2020 , reflects Aflac U.S. favorable claims experience compared to previous estimates, primarily in the cancer and accident lines of business.

REINSURANCE

REINSURANCE	3 Months Ended
	Mar. 31, 2020
Reinsurance Disclosures [Abstract]
REINSURANCE	REINSURANCE The Company periodically enters into fixed quota-share coinsurance agreements with other companies in the normal course of business. For each of its reinsurance agreements, the Company determines whether the agreement provides indemnification against loss or liability relating to insurance risk in accordance with applicable accounting standards. Reinsurance premiums and benefits paid or provided are accounted for on bases consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Premiums and benefits are reported net of insurance ceded. The Company has recorded a deferred profit liability related to reinsurance transactions. The remaining deferred profit liability of $1.0 billion as of both March 31, 2020 and December 31, 2019 , respectively, is included in future policy benefits in the consolidated balance sheet and is being amortized into income over the expected lives of the policies. The Company has also recorded a reinsurance recoverable for reinsurance transactions, which is included in other assets in the consolidated balance sheet and had a remaining balance of $976 million and $970 million as of March 31, 2020 and December 31, 2019 , respectively. The increase in the reinsurance recoverable balance was driven by the growth in reserves related to the business that has been reinsured as the policies age. The spot yen/dollar exchange rate strengthened by approximately .7% and ceded reserves increased approximately 2.3% from December 31, 2019 to March 31, 2020 . The following table reconciles direct premium income and direct benefits and claims to net amounts after the effect of reinsurance. Three Months Ended (In millions) 2020 2019 Direct premium income $ 4,772 $ 4,776 Ceded to other companies: Ceded Aflac Japan closed blocks (116 ) (121 ) Other (24 ) (15 ) Assumed from other companies: Retrocession activities 49 50 Other 0 1 Net premium income $ 4,681 $ 4,691 Direct benefits and claims $ 3,028 $ 3,041 Ceded benefits and change in reserves for future benefits: Ceded Aflac Japan closed blocks (105 ) (111 ) Eliminations 10 10 Other (25 ) (11 ) Assumed from other companies: Retrocession activities 41 48 Eliminations (10 ) (10 ) Other 0 0 Benefits and claims, net $ 2,939 $ 2,967 These reinsurance transactions are indemnity reinsurance that do not relieve the Company from its obligations to policyholders. In the event that the reinsurer is unable to meet their obligations, the Company remains liable for the reinsured claims. As a part of its capital contingency plan, the Company entered into a committed reinsurance facility agreement on December 1, 2015 in the amount of approximately ¥110 billion of reserves. This reinsurance facility agreement was renewed in 2019 and is effective until December 31, 2020. There are also additional commitment periods of a one-year duration, each of which are automatically extended unless notification is received from the reinsurer within 60 days prior to the expiration. The reinsurer can withdraw from the committed facility if Aflac‘s Standard and Poor's (S&P) rating drops below BBB-. As of March 31, 2020 , the Company has not executed a reinsurance treaty under this committed reinsurance facility.

NOTES PAYABLE AND LEASE OBLIGAT

NOTES PAYABLE AND LEASE OBLIGATIONS	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
NOTES PAYABLE AND LEASE OBLIGATIONS	NOTES PAYABLE AND LEASE OBLIGATIONS A summary of notes payable and lease obligations follows: (In millions) March 31, 2020 December 31, 2019 4.00% senior notes paid January 2020 $ 0 $ 348 3.625% senior notes due June 2023 698 698 3.625% senior notes due November 2024 747 747 3.25% senior notes due March 2025 448 448 2.875% senior notes due October 2026 298 298 6.90% senior notes due December 2039 220 220 6.45% senior notes due August 2040 254 254 4.00% senior notes due October 2046 393 394 4.750% senior notes due January 2049 541 541 Yen-denominated senior notes and subordinated debentures: .300% senior notes due September 2025 (principal amount ¥ 12.4 billion) 113 0 .932% senior notes due January 2027 (principal amount ¥60.0 billion) 549 545 .500% senior notes due December 2029 (principal amount ¥12.6 billion) 115 114 .550% senior notes due March 2030 (principal ¥ 13.3 billion) 121 0 1.159% senior notes due October 2030 (principal amount ¥29.3 billion) 268 266 .843% senior notes due December 2031 (principal amount ¥9.3 billion) 85 84 .750% senior notes due March 2032 (principal amount ¥20.7 billion) 189 0 1.488% senior notes due October 2033 (principal amount ¥15.2 billion) 139 138 .934% senior notes due December 2034 (principal amount ¥9.8 billion) 89 88 .830% senior notes due March 2035 (principal amount ¥10.6 billion) 97 0 1.750% senior notes due October 2038 (principal amount ¥8.9 billion) 81 81 1.122% senior notes due December 2039 (principal amount ¥6.3 billion) 57 57 2.108% subordinated debentures due October 2047 (principal amount ¥60.0 billion) 547 543 .963% subordinated bonds due April 2049 (principal amount ¥30.0 billion) 274 272 Yen-denominated loans: Variable interest rate loan due September 2026 (.42% in 2020 and 2019, principal amount ¥5.0 billion) 46 45 Variable interest rate loan due September 2029 (.57% in 2020 and 2019, principal amount ¥25.0 billion) 228 227 Finance lease obligations payable through 2026 12 12 Operating lease obligations payable through 2028 149 149 Total notes payable and lease obligations $ 6,758 $ 6,569 Amounts in the table above are reported net of debt issuance costs and issuance premiums or discounts, if applicable, that are being amortized over the life of the notes. In March 2020, the Parent Company issued four series of senior notes totaling ¥57.0 billion through a public debt offering under its U.S. shelf registration statement. The first series, which totaled ¥12.4 billion , bears interest at a fixed rate of .300% per annum, payable semi­annually and will mature in September 2025. The second series, which totaled ¥13.3 billion , bears interest at a fixed rate of .550% per annum, payable semi-annually, and will mature in March 2030. The third series, which totaled ¥20.7 billion , bears interest at a fixed rate of .750% per annum, payable semi­annually and will mature in March 2032. The fourth series, which totaled ¥10.6 billion , bears interest at a fixed rate of .830% per annum, payable semi-annually, and will mature in March 2035. These notes may only be redeemed before maturity, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance. In January 2020, the Parent Company used the net proceeds from senior notes issued in December 2019 to redeem $350 million of its 4.00% fixed-rate senior notes due February 2022. A summary of the Company's lines of credit as of March 31, 2020 follows: Borrower(s) Type Term Expiration Date Capacity Amount Outstanding Interest Rate on Borrowed Amount Maturity Period Commitment Fee Business Purpose Aflac Incorporated uncommitted bilateral 364 days December 18, 2020 $100 million $0 million The rate quoted by the bank and agreed upon at the time of borrowing Up to 3 months None General corporate purposes Aflac Incorporated unsecured revolving 5 years March 29, 2024, or the date commitments are terminated pursuant to an event of default ¥100.0 billion ¥0.0 billion A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out period No later than .30% to .50%, depending on the Parent Company's debt ratings as of the date of determination General corporate purposes, including a capital contingency plan for the operations of the Parent Company Aflac Incorporated unsecured revolving 5 years November 18, 2024, or the date commitments are terminated pursuant to an event of default $1.0 billion $0.0 billion A rate per annum equal to, at the Company's option, either, (a) LIBOR adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin No later than November 18, 2024 .085% to .225%, depending on the Parent Company's debt ratings as of the date of determination General corporate purposes, including a capital contingency plan for the operations of the Parent Company Aflac Incorporated uncommitted bilateral None specified None specified $50 million $0 million A rate per annum equal to, at the Parent Company's option, either (a) a eurocurrency rate determined by reference to the agent's LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the greater of (i) the prime rate as determined by the agent, and (ii) the sum of 0.50% and the federal funds rate for such day Up to 3 months None General corporate purposes Aflac (1) uncommitted revolving 364 days November 30, 2020 $250 million $82 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes Aflac Incorporated (1) uncommitted revolving 364 days April 2, 2020 (2) ¥50.0 billion ¥0.0 billion Three-month TIBOR plus 70 basis points per annum 3 months None General corporate purposes Aflac Incorporated (1) uncommitted revolving 364 days November 25, 2020 ¥50.0 billion ¥0.0 billion Three-month TIBOR plus 70 basis points per annum 3 months None General corporate purposes Aflac New York (1) uncommitted revolving 364 days March 20, 2021 $25 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes CAIC (1) uncommitted revolving 364 days March 20, 2021 $15 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes Tier One Insurance Company (1) uncommitted revolving 364 days March 20, 2021 $.3 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes (1) Intercompany credit agreement (2) Renewed in April 2020 with an expiration date of April 2, 2021 The Company was in compliance with all of the covenants of its notes payable and lines of credit at March 31, 2020 . No events of default or defaults occurred during the three -month period ended March 31, 2020 . For additional information, see Notes 4 and 9 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report.

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security (CARES) Act was signed into law and includes certain income tax provisions relevant to businesses. The Company is required to recognize the effect on the consolidated financial statements in the period the law was enacted, which is the period ended March 31, 2020. For the period ended March 31, 2020, the CARES Act did not have a material impact on the Company’s consolidated financial statements. At this time, the Company does not expect the impact of the CARES Act to have a material impact on the Company’s consolidated financial statements for the year ended December 31, 2020. The Company’s combined U.S. and Japanese effective income tax rate on pretax earnings was 21.4% for the three-month period ended March 31, 2020, compared with 25.3% for the same period in 2019. This combined effective tax rate differs from the U.S. statutory rate primarily due to foreign earnings taxed at different rates. The primary driver for the reduced income tax rate in the current period is the pretax investment losses in Japan, which provide a 28% income tax benefit.

SHAREHOLDERS' EQUITY

SHAREHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
SHAREHOLDERS' EQUITY	SHAREHOLDERS’ EQUITY The following table is a reconciliation of the number of shares of the Company's common stock for the three -month periods ended March 31 . (In thousands of shares) 2020 2019 Common stock - issued: Balance, beginning of period 1,349,309 1,347,540 Exercise of stock options and issuance of restricted shares 1,341 1,060 Balance, end of period 1,350,650 1,348,600 Treasury stock: Balance, beginning of period 622,516 592,254 Purchases of treasury stock: Share repurchase program 9,984 10,237 Other 508 561 Dispositions of treasury stock: Shares issued to AFL Stock Plan (468 ) (430 ) Exercise of stock options (45 ) (231 ) Other (227 ) (278 ) Balance, end of period 632,268 602,113 Shares outstanding, end of period 718,382 746,487 Outstanding share-based awards are excluded from the calculation of weighted-average shares used in the computation of basic earnings per share (EPS). The following table presents the approximate number of share-based awards to purchase shares, on a weighted-average basis, that were considered to be anti-dilutive and were excluded from the calculation of diluted earnings per share for the following periods. Three Months Ended (In thousands) 2020 2019 Anti-dilutive share-based awards 744 22 Share Repurchase Program During the first three months of 2020 , the Company repurchased 10.0 million shares of its common stock for $449 million as part of its share repurchase program. During the first three months of 2019 , the Company repurchased 10.2 million shares of its common stock for $490 million as part of its share repurchase program. As of March 31, 2020 , a remaining balance of 27.1 million shares of the Company's common stock was available for purchase under share repurchase authorizations by its board of directors. Reclassifications from Accumulated Other Comprehensive Income The tables below are reconciliations of accumulated other comprehensive income by component for the following periods. Changes in Accumulated Other Comprehensive Income Three Months Ended (In millions) Unrealized Foreign Unrealized Unrealized Pension Total Balance at December 31, 2019 $ (1,623 ) $ 8,548 $ (33 ) $ (277 ) $ 6,615 Cumulative effect of change 0 848 0 0 848 Balance at January 1, 2020 $ (1,623 ) $ 9,396 $ (33 ) $ (277 ) $ 7,463 Other comprehensive 80 (3,359 ) (2 ) (6 ) (3,287 ) Amounts reclassified from 0 6 0 6 12 Net current-period other 80 (3,353 ) (2 ) 0 (3,275 ) Balance at March 31, 2020 $ (1,543 ) $ 6,043 $ (35 ) $ (277 ) $ 4,188 All amounts in the table above are net of tax. Three Months Ended (In millions) Unrealized Foreign Unrealized Unrealized Pension Liability Adjustment Total Balance at December 31, 2018 $ (1,847 ) $ 4,234 $ (24 ) $ (212 ) $ 2,151 Other comprehensive (1 ) 2,340 (2 ) 3 2,340 Amounts reclassified from 0 (13 ) 0 3 (10 ) Net current-period other (1 ) 2,327 (2 ) 6 2,330 Balance at March 31, 2019 $ (1,848 ) $ 6,561 $ (26 ) $ (206 ) $ 4,481 All amounts in the table above are net of tax. The tables below summarize the amounts reclassified from each component of accumulated other comprehensive income into net earnings for the following periods. Reclassifications Out of Accumulated Other Comprehensive Income (In millions) Three Months Ended Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Unrealized gains (losses) on available-for-sale $ (7 ) Net investment gains (losses) 1 Tax (expense) or benefit (1) $ (6 ) Net of tax Amortization of defined benefit pension items: Actuarial gains (losses) $ (8 ) Acquisition and operating expenses (2) Prior service (cost) credit 0 Acquisition and operating expenses (2) 2 Tax (expense) or benefit (1) $ (6 ) Net of tax Total reclassifications for the period $ (12 ) Net of tax (1) Based on 21% blended tax rate (2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 12 for additional details). (In millions) Three Months Ended Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Unrealized gains (losses) on available-for-sale $ 17 Net investment gains (losses) (4 ) Tax (expense) or benefit (1) $ 13 Net of tax Amortization of defined benefit pension items: Actuarial gains (losses) $ (4 ) Acquisition and operating expenses (2) Prior service (cost) credit 0 Acquisition and operating expenses (2) 1 Tax (expense) or benefit (1) $ (3 ) Net of tax Total reclassifications for the period $ 10 Net of tax (1) Based on 25% blended tax rate (2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 12 for additional details).

SHARE-BASED COMPENSATION

SHARE-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
SHARE-BASED COMPENSATION	SHARE-BASED COMPENSATION As of March 31, 2020 , the Company has outstanding share-based awards under the Aflac Incorporated Long-Term Incentive Plan (the Plan). Share-based awards are designed to reward employees for their long-term contributions to the Company and provide incentives for them to remain with the Company. The number and frequency of share-based awards are based on competitive practices, operating results of the Company, government regulations, and other factors. The Plan, as amended on February 14, 2017, allows for a maximum number of shares issuable over its term of 75 million shares including 38 million shares that may be awarded in respect of awards other than options or stock appreciation rights. If any awards granted under the Plan are forfeited or are terminated before being exercised or settled for any reason other than tax forfeiture, then the shares underlying the awards will again be available under the Plan. The Plan allows awards to Company employees for incentive stock options (ISOs), non-qualifying stock options (NQSOs), restricted stock, restricted stock units, and stock appreciation rights. Non-employee directors are eligible for grants of NQSOs, restricted stock, and stock appreciation rights. As of March 31, 2020 , approximately 38.0 million shares were available for future grants under this plan. The ISOs and NQSOs have a term of 10 years , and the share-based awards generally vest upon time-based conditions or time and performance-based conditions. Time-based vesting generally occurs after three years . Performance-based vesting conditions generally include the attainment of goals related to Company financial performance. As of March 31, 2020 , the only performance-based awards issued and outstanding were restricted stock awards and units. Stock options and stock appreciation rights granted under the amended Plan have an exercise price of at least the fair market value of the underlying stock on the grant date and have an expiration date no later than 10 years from the grant date. Time-based restricted stock awards, restricted stock units and stock options granted after January 1, 2017 generally vest on a ratable basis over three years , and awards granted prior to the amendment vest on a three years cliff basis. The Compensation Committee of the Board of Directors has the discretion to determine vesting schedules . Share-based awards granted to U.S.-based grantees are settled with authorized but unissued Company stock, while those issued to Japan-based grantees are settled with treasury shares. The following table provides information on stock options outstanding and exercisable at March 31, 2020 . Stock Weighted-Average Aggregate Weighted-Average Outstanding 3,354 4.4 $ 16 $ 29.98 Exercisable 3,353 4.4 16 29.97 The Company received cash from the exercise of stock options in the amount of $6 million during the first three months of 2020 , compared with $17 million in the first three months of 2019 . The tax benefit realized as a result of stock option exercises and restricted stock releases was $17 million in the first three months of 2020 , compared with $22 million in the first three months of 2019 . As of March 31, 2020 , total compensation cost not yet recognized in the Company's financial statements related to restricted stock awards was $72 million , of which $35 million ( 1.7 million shares) was related to restricted stock awards with a performance-based vesting condition. The Company expects to recognize these amounts over a weighted-average period of approximately 2.5 years . There are no other contractual terms covering restricted stock awards once vested. The following table summarizes restricted stock activity during the three -month period ended March 31, 2020 . (In thousands of shares) Shares Weighted-Average Grant-Date Fair Value Per Share Restricted stock at December 31, 2019 2,573 $ 44.66 Granted in 2020 1,376 46.66 Canceled in 2020 (25 ) 46.52 Vested in 2020 (1,358 ) 38.48 Restricted stock at March 31, 2020 2,566 $ 48.97 In February 2020, the Company granted 409 thousand performance-based stock awards, which are contingent on the achievement of the Company's financial performance metrics and its market-based conditions. On the date of grant, the Company estimated the fair value of restricted stock awards with market-based conditions using a Monte Carlo simulation model. The model discounts the value of the stock at the assumed vesting date based on the risk-free interest rate. Based on estimates of actual performance versus the vesting thresholds, the calculated fair value percentage pay-out estimate will be updated each quarter. The Company uses third-party analyses to assist in developing the assumptions used in, as well as calibrating, a Monte Carlo simulation model. The Company is responsible for determining the assumptions used in estimating the fair value of its share-based payment awards. For additional information on the Company's long-term share-based compensation plans and the types of share-based awards, see Note 12 of the Notes to the Consolidated Financial Statements included in the 2019 Annual Report.

BENEFIT PLANS

BENEFIT PLANS	3 Months Ended
	Mar. 31, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
BENEFIT PLANS	BENEFIT PLANS The Company has funded defined benefit plans in Japan and the U.S., however the U.S. plan was frozen to new participants effective October 1, 2013. The Company also maintains non-qualified, unfunded supplemental retirement plans that provide defined pension benefits in excess of limits imposed by federal tax law for certain Japanese, U.S. and former employees, however the U.S. plan was frozen to new participants effective January 1, 2015. U.S. employees who are not participants in the defined benefit plan receive a nonelective 401(k) employer contribution. The Company provides certain health care benefits for eligible U.S. retired employees, their beneficiaries and covered dependents (other postretirement benefits). The health care plan is contributory and unfunded. Effective January 1, 2014, employees eligible for benefits included the following: (1) active employees whose age plus service, in years, equaled or exceeded 80 (rule of 80 ); (2) active employees who were age 55 or older and have met the 15 years of service requirement; (3) active employees who would meet the rule of 80 in the next 5 years ; (4) active employees who were age 55 or older and who would meet the 15 years of service requirement within the next 5 years ; and (5) current retirees. For certain employees and former employees, additional coverage is provided for all medical expenses for life. Pension and other postretirement benefit expenses are included in acquisition and operating expenses in the consolidated statement of earnings, which includes other components of net periodic pension cost and postretirement costs (other than service costs) of $6 million and $5 million for the three -month periods ended March 31, 2020 and 2019 , respectively. Total net periodic cost includes the following components: Three Months Ended March 31, Pension Benefits Other Japan U.S. Postretirement Benefits (In millions) 2020 2019 2020 2019 2020 2019 Components of net periodic Service cost $ 6 $ 5 $ 7 $ 6 $ 0 $ 0 Interest cost 1 1 8 9 0 0 Expected return on plan (2 ) (2 ) (9 ) (7 ) 0 0 Amortization of net actuarial 1 1 6 3 1 0 Net periodic (benefit) cost $ 6 $ 5 $ 12 $ 11 $ 1 $ 0 During the three months ended March 31, 2020 , Aflac Japan contributed approximately $9 million (using the weighted-average yen/dollar exchange rate for the three -month period ending March 31, 2020 ) to the Japanese funded defined benefit plan, and Aflac U.S. did not make a contribution to the U.S. funded defined benefit plan. For additional information regarding the Company's Japanese and U.S. benefit plans, see Note 14 of the Notes to the Consolidated Financial Statements in the 2019 Annual Report.

COMMITMENTS AND CONTINGENT LIAB

COMMITMENTS AND CONTINGENT LIABILITIES	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENT LIABILITIES	COMMITMENTS AND CONTINGENT LIABILITIES The Company is a defendant in various lawsuits considered to be in the normal course of business. Members of the Company's senior legal and financial management teams review litigation on a quarterly and annual basis. The final results of any litigation cannot be predicted with certainty. Although some of this litigation is pending in states where large punitive damages, bearing little relation to the actual damages sustained by plaintiffs, have been awarded in recent years, the Company believes the outcome of pending litigation will not have a material adverse effect on its financial position, results of operations, or cash flows. See Note 3 of the Notes to the Consolidated Financial Statements for details on certain investment commitments. Guaranty Fund Assessments The U.S. insurance industry has a policyholder protection system that is monitored and regulated by state insurance departments. These life and health insurance guaranty associations are state entities (in all 50 states as well as Puerto Rico and the District of Columbia) created to protect policyholders of an insolvent insurance company. All insurance companies (with limited exceptions) licensed to sell life or health insurance in a state must be members of that state’s guaranty association. Under state guaranty association laws, certain insurance companies can be assessed (up to prescribed limits) for certain obligations to the policyholders and claimants of impaired or insolvent insurance companies that write the same line or similar lines of business. In 2009, the Pennsylvania Insurance Commissioner placed long-term care insurer Penn Treaty Network America Insurance Company and its subsidiary American Network Insurance Company (collectively referred to as Penn Treaty), neither of which is affiliated with Aflac, in rehabilitation and petitioned a state court for approval to liquidate Penn Treaty. A final order of liquidation was granted by a recognized judicial authority on March 1, 2017, and as a result, Penn Treaty is in the process of liquidation. The Company estimated and recognized the impact of its share of guaranty fund assessments resulting from the liquidation using a discounted rate of 4.25% . The Company recognized a discounted liability for the assessments of $62 million (undiscounted $94 million ), offset by discounted premium tax credits of $48 million (undiscounted $74 million ), for a net $14 million impact to net income in the quarter ended March 31, 2017. The Company paid a majority of these assessments by March 31, 2020. The Company used the cost estimate provided as of the liquidation date by the National Organization of Life and Health Guaranty Associations (NOLHGA) to calculate its estimated assessments and tax credits. Guaranty fund assessments for the three -month period ended March 31, 2020 were immaterial.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS In April 2020, the Parent Company issued $1.0 billion of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.60% per annum, payable semi-annually, and will mature in April 2030. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 45 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) primarily sell supplemental health and life insurance in the United States (U.S.) and Japan. The Company’s operations consist of two reportable business segments: Aflac Japan and Aflac U.S. The Parent Company's primary insurance subsidiaries are Aflac Life Insurance Japan Ltd. (Aflac Japan) and American Family Life Assurance Company of Columbus (Aflac); Continental American Insurance Company (CAIC), branded as Aflac Group Insurance (AGI); American Family Life Assurance Company of New York (Aflac New York); Tier One Insurance Company (TOIC) and Argus Dental & Vision, Inc (Argus), which provides a platform for Aflac Dental and Vision in the U.S. (collectively, Aflac U.S.). Aflac Japan's revenues, including net gains and losses on its investment portfolio, accounted for 67% and 68% of the Company's total revenues in the three -month periods ended March 31, 2020 and 2019 , respectively. The percentage of the Company's total assets attributable to Aflac Japan was 84% at March 31, 2020 and December 31, 2019 , respectively. Basis of Presentation The Company prepares its financial statements in accordance with U.S. generally accepted accounting principles (U.S. GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to U.S. GAAP issued by the FASB are derived from the FASB Accounting Standards Codification TM (ASC). The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates based on currently available information when recording transactions resulting from business operations. The most significant items on the Company's balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments and derivatives, deferred policy acquisition costs (DAC), liabilities for future policy benefits and unpaid policy claims, and income taxes. These accounting estimates and actuarial determinations are sensitive to market conditions, investment yields, mortality, morbidity, commission and other acquisition expenses, and terminations by policyholders. As additional information becomes available, or actual amounts are determinable, the recorded estimates will be revised and reflected in operating results. Although some variability is inherent in these estimates, the Company believes the amounts provided are adequate. The unaudited consolidated financial statements include the accounts of the Parent Company, its subsidiaries and those entities required to be consolidated under applicable accounting standards. All material intercompany accounts and transactions have been eliminated. In the opinion of management, the accompanying unaudited consolidated financial statements of the Company contain all adjustments, consisting of normal recurring accruals, which are necessary to fairly present the consolidated balance sheets as of March 31, 2020 , and December 31, 2019 , and the consolidated statements of earnings and comprehensive income (loss), shareholders' equity and cash flows for the three -month periods ended March 31, 2020 and 2019 . Results of operations for interim periods are not necessarily indicative of results for the entire year. As a result, these financial statements should be read in conjunction with the financial statements and notes thereto included in the Company's annual report on Form 10-K for the year ended December 31, 2019 ( 2019 Annual Report). COVID-19: On March 11, 2020, the World Health Organization declared the COVID-19 outbreak a global pandemic. The impact of COVID-19 on the Company is evolving and its future effects are uncertain and the Company is closely monitoring the effects and risks of COVID-19 to assess its impact on the Company's business, financial condition, results of operations, liquidity and capital position. Liquidity and Capital Resources The Company entered the crisis having maintained capital ratios in Japan and the U.S. at a level designed to absorb a degree of market volatility. To further support liquidity and capital resources, the Parent Company, in March 2020, issued four series of senior notes totaling ¥57.0 billion and, in April 2020, issued $1 billion in senior notes through public debt offerings under its U.S. shelf registration statement. The Company has available liquidity in its unsecured revolving credit facilities of $1.0 billion and ¥100.0 billion , respectively, and currently has no borrowings under either of these facilities. In April 2020, Aflac increased its internal limit for Federal Home Loan Bank of Atlanta (FHLB) borrowings to $800 million , $300 million of which the Company has designated to be used for short-term liquidity needs and subject to qualified collateral availability and other conditions. The Company continues to evaluate other sources of liquidity including reinvestment cash flows and selling investments. Major government initiatives Government authorities in Japan and the U.S. have implemented several initiatives in response to the COVID-19 pandemic, including actions designed to mitigate the adverse health effects of the virus and those designed to provide broad-based relief and economic support to all aspects of the economy. Given that these measures were recently implemented, it is too early to determine what impacts these initiatives will have on the Company’s business, results of operations, financial condition, liquidity, capital position, investment portfolio, workforce, distribution partners and vendors.
Reclassifications	Reclassifications : Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. These reclassifications had no impact on net earnings or total shareholders' equity.
Recently Adopted Accounting Pronouncements	Standard Description Date of Adoption Effect on Financial Statements or Other Significant Matters Accounting Standards Update (ASU) 2019-04 Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments In April 2019, the FASB issued Codification improvements to clarify and correct certain areas of guidance amended as part of ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2016-13 , Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments; and ASU 2017-12 , Derivative and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. The most significant of these improvements to the Company was related to the Codification improvement to ASU 2017-12 and the clarification that a one-time reclassification of assets that are eligible to be hedged under the last-of-layer method (i.e., certain pre-payable securities) from held-to-maturity to available-for-sale is allowed under the new hedge accounting guidance and would not impact the Company’s ability to continue to classify other bonds as held-to-maturity. The other amendments related to ASU 2017-12 and 2016-01 are either not significant, or were previously implemented as part of the related ASU adoptions. Applicable amendments related to ASU 2016-13 are discussed within the recent adoption of that update below. January 1, 2020 The adoption of this guidance resulted in a reclassification of $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity to the available-for-sale category. The reclassification resulted in recording in accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis, based on the securities’ fair values on the reclassification date. The reclassification impacted the adoption of ASU 2016-13 (see ASU 2016-13 below for additional details). ASU 2018-17 Consolidation: Targeted Improvements to Related Party Guidance for Variable Interest Entities In October 2018, the FASB issued targeted improvements which provide that indirect interests held through related parties under common control should be considered on a proportional basis for determining whether fees paid to decision makers and service providers are variable interests. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2018-13 Fair Value Measurement, Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued amendments to the disclosure requirements on fair value measurements. The amendments remove, modify, and add certain disclosures. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company’s financial position, results of operations, or disclosures. Standard Description Date of Adoption Effect on Financial Statements or Other Significant Matters ASU 2017-04 Intangibles - Goodwill and Other: Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued amendments simplifying the subsequent measurement of goodwill. An entity, under this update, is no longer required to perform a hypothetical purchase price allocation to measure goodwill impairment. Instead, the entity should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. January 1, 2020 The adoption of this guidance did not have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2016-13 Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments as clarified and amended by: ASU 2019-04 , Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, ASU 2019-05 , Financial Instruments - Credit Losses (Topic 326), Targeted Transition Relief and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments- Credit Losses In June 2016, the FASB issued amendments that require a financial asset (or a group of financial assets) measured at amortized cost to be presented net of an allowance for credit losses (Credit Losses ASU) in order to reflect the amount expected to be collected on the financial asset(s). The measurement of expected credit losses is amended by replacing the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information. Credit losses on available-for-sale debt securities will be measured in a manner similar to current U.S. GAAP; however, the amendments require that credit losses be presented as an allowance rather than as a write-down. Other amendments include changes to the balance sheet presentation and interest income recognition of purchased financial assets with a more-than-insignificant credit deterioration since origination (PCD financial assets). January 1, 2020 The Company recorded a cumulative effect adjustment with a decrease to beginning 2020 retained earnings of $56 million, net of taxes. See Note 3 of the Notes to the Consolidated Financial Statements for credit loss disclosures. The following line items in the consolidated balance sheets were most significantly impacted by the adoption of the new accounting standard: • Fixed maturity securities held to maturity, at amortized cost • Commercial mortgage and other loans • Reinsurance recoverable, included within Other assets
Description of Accounting Pronouncements Pending Adoption	Standard Description Effect on Financial Statements or Other Significant Matters ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting In March 2020, the FASB issued amendments that provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this ASU only apply to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. An entity may elect to apply the amendments as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. The Company is thoroughly evaluating the adoption of this guidance and the impact on the Company’s financial position, results of operations, and disclosures. ASU 2020-01 Clarifying the interactions between Topic 321, Topic 323, and Topic 815 In January 2020, the FASB issued amendments clarifying that an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting for the purposes of applying the measurement alternative in accordance with Topic 321 immediately before applying or upon discontinuing the equity method. In addition, the amendments clarify that for the purpose of applying certain derivative guidance in Topic 815, an entity should not consider whether, upon the settlement of the forward contract or exercise of the purchased option, individually or with existing investments, the underlying securities would be accounted for under the equity method in Topic 323 or the fair value option in accordance with the financial instruments guidance in Topic 825. An entity also would evaluate the remaining characteristics in Topic 815 to determine the accounting for those forward contracts and purchased options. The amendments are effective for public business entities for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. Early adoption is permitted. The adoption of this guidance is not expected to have a significant impact on the Company's financial position, results of operations, or disclosures. ASU 2018-12 Financial Services - Insurance, Targeted Improvements to the Accounting for Long-Duration Contracts as clarified and amended by: ASU 2019-09 Financial Services - Insurance (Topic 944): Effective Date In August 2018, the FASB issued amendments that will significantly change how insurers account for long-duration contracts. The amendments will change existing recognition, measurement, presentation, and disclosure requirements. Issues addressed in the new guidance include: 1) a requirement to review and, if there is a change, update assumptions for the liability for future policy benefits at least annually, and to update the discount rate assumption quarterly, 2) accounting for market risk benefits at fair value, 3) simplified amortization for deferred acquisition costs, and 4) enhanced financial statement presentation and disclosures. The amendments are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. In November 2019, the FASB issued an amendment extending the effective date for public business entities that meet the definition of an SEC filer, excluding entities eligible to be small reporting companies as defined by the SEC, by one year. The amendments are now effective for the Company for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021. Early application of the amendments is permitted. The Company is thoroughly evaluating the impact of adoption and expects that the adoption will have a significant impact on the Company’s financial position, results of operations, and disclosures. The Company anticipates that the requirement to update assumptions for liability for future policy benefits will have a significant impact on its results of operations, systems, processes and controls while the requirement to update the discount rate will have a significant impact on its equity. The Company has no products with market risk benefits. The Company does not expect to early adopt the updated standard and has tentatively selected a modified retrospective transition method.

BUSINESS SEGMENT INFORMATION (T

BUSINESS SEGMENT INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Reconciliation of Revenue from Segments to Consolidated	Information regarding operations by reportable segment and Corporate and other, follows: Three Months Ended (In millions) 2020 2019 Revenues: Aflac Japan: Net earned premiums $ 3,150 $ 3,180 Adjusted net investment income (1),(2) 642 610 Other income 11 12 Total adjusted revenue Aflac Japan 3,803 3,802 Aflac U.S.: Net earned premiums 1,483 1,461 Net investment income 177 177 Other income 27 2 Total adjusted revenue Aflac U.S. 1,687 1,640 Corporate and other (3) 104 95 Total adjusted revenues 5,594 5,537 Net investment gains (losses) (1),(2),(3) (432 ) 120 Total revenues $ 5,162 $ 5,657 (1) Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations. (2) Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income. (3) Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
Reconciliation of Adjusted Profit (Loss) from Segments to Consolidated	Three Months Ended (In millions) 2020 2019 Pretax adjusted earnings: Aflac Japan (1),(2) $ 855 $ 834 Aflac U.S. 326 323 Corporate and other (3),(4) 2 (18 ) Pretax adjusted earnings (5) 1,183 1,139 Net investment gains (losses) (1),(2),(3),(4) (448 ) 103 Other income (loss) (15 ) 0 Total earnings before income taxes $ 720 $ 1,242 Income taxes applicable to pretax adjusted earnings $ 301 $ 291 Effect of foreign currency translation on after-tax 9 (8 ) (1) Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations. (2) Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income. (3) Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase in net investment income when analyzing operations. (4) A gain of $16 and $17 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations. (5) Includes $33 for the three-month periods ended March 31, 2020 , and 2019 , respectively, of interest expense on debt.
Reconciliation of Assets from Segment to Consolidated	Assets were as follows: (In millions) March 31, December 31, Assets: Aflac Japan $ 126,955 $ 127,523 Aflac U.S. 20,526 20,945 Corporate and other 4,135 4,300 Total assets $ 151,616 $ 152,768

INVESTMENTS (Tables)

INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Available-for-Sale Debt Securities	The amortized cost for the Company's investments in fixed maturity securities, the cost for equity securities and the fair values of these investments are shown in the following tables. March 31, 2020 (In millions) Allowance for Credit Losses Gross Gross Fair Securities available for sale, carried at fair Fixed maturity securities: Yen-denominated: Japan government and agencies $ 31,853 $ 0 $ 4,766 $ 14 $ 36,605 Municipalities 984 0 228 1 1,211 Mortgage- and asset-backed securities 306 0 31 0 337 Public utilities 4,412 0 430 93 4,749 Sovereign and supranational 1,300 0 33 27 1,306 Banks/financial institutions 7,159 0 404 557 7,006 Other corporate 7,817 0 753 389 8,181 Total yen-denominated 53,831 0 6,645 1,081 59,395 U.S. dollar-denominated: U.S. government and agencies 350 0 23 0 373 Municipalities 1,084 0 145 0 1,229 Mortgage- and asset-backed securities 152 0 8 0 160 Public utilities 3,844 0 649 50 4,443 Sovereign and supranational 239 0 65 1 303 Banks/financial institutions 2,848 0 545 21 3,372 Other corporate 25,533 63 2,531 988 27,013 Total U.S. dollar-denominated 34,050 63 3,966 1,060 36,893 Total securities available for sale $ 87,881 $ 63 $ 10,611 $ 2,141 $ 96,288 December 31, 2019 (In millions) Gross Gross Fair Securities available for sale, carried at fair value through other comprehensive income: Fixed maturity securities: Yen-denominated: Japan government and agencies $ 30,929 $ 5,169 $ 0 $ 36,098 Municipalities 516 116 3 629 Mortgage- and asset-backed securities 229 25 0 254 Public utilities 1,855 406 0 2,261 Sovereign and supranational 680 50 0 730 Banks/financial institutions 6,152 700 86 6,766 Other corporate 5,323 944 24 6,243 Total yen-denominated 45,684 7,410 113 52,981 U.S dollar-denominated: U.S. government and agencies 293 9 0 302 Municipalities 1,077 141 0 1,218 Mortgage- and asset-backed securities 149 7 0 156 Public utilities 3,804 725 10 4,519 Sovereign and supranational 239 73 0 312 Banks/financial institutions 2,879 646 4 3,521 Other corporate 25,246 3,255 248 28,253 Total U.S. dollar-denominated 33,687 4,856 262 38,281 Total securities available for sale $ 79,371 $ 12,266 $ 375 $ 91,262
Held-to-maturity Securities	March 31, 2020 (In millions) Allowance for Credit Losses Net Carrying Amount Gross Gross Fair Securities held to maturity, carried at Fixed maturity securities: Yen-denominated: Japan government and agencies $ 22,387 $ 3 $ 22,384 $ 5,810 $ 0 $ 28,194 Municipalities 362 0 362 122 0 484 Public utilities 46 1 45 14 0 59 Sovereign and supranational 469 5 464 114 0 578 Other corporate 23 0 23 9 0 32 Total yen-denominated 23,287 9 23,278 6,069 0 29,347 Total securities held to maturity $ 23,287 $ 9 $ 23,278 $ 6,069 $ 0 $ 29,347 December 31, 2019 (In millions) Gross Gross Fair Securities held to maturity, carried at Fixed maturity securities: Yen-denominated: Japan government and agencies $ 22,241 $ 6,050 $ 0 $ 28,291 Municipalities 821 262 0 1,083 Mortgage- and asset-backed securities 16 1 0 17 Public utilities 2,535 419 0 2,954 Sovereign and supranational 1,123 197 0 1,320 Banks/financial institutions 916 105 3 1,018 Other corporate 2,433 485 7 2,911 Total yen-denominated 30,085 7,519 10 37,594 Total securities held to maturity $ 30,085 $ 7,519 $ 10 $ 37,594
Equity securities, FV-NI	(In millions) March 31, 2020 December 31, 2019 Equity securities, carried at fair value through net earnings: Fair Value Fair Value Equity securities: Yen-denominated $ 528 $ 658 U.S. dollar-denominated 132 144 Total equity securities $ 660 $ 802
Investments Classified by Contractual Maturity Date	The contractual and economic maturities of the Company's investments in fixed maturity securities at March 31, 2020 , were as follows: (In millions) Amortized (1) Fair Available for sale: Due in one year or less $ 1,078 $ 1,105 Due after one year through five years 8,992 8,806 Due after five years through 10 years 12,399 13,221 Due after 10 years 64,891 72,659 Mortgage- and asset-backed securities 458 497 Total fixed maturity securities available for sale $ 87,818 $ 96,288 Held to maturity: Due in one year or less $ 0 $ 0 Due after one year through five years 0 0 Due after five years through 10 years 49 55 Due after 10 years 23,229 29,292 Mortgage- and asset-backed securities 0 0 Total fixed maturity securities held to maturity $ 23,278 $ 29,347 (1) Net of allowance for credit losses
Investment Exposures Exceeding Ten Percent Shareholders Equity	Investment exposures that individually exceeded 10% of shareholders' equity were as follows: March 31, 2020 December 31, 2019 (In millions) Credit Amortized Fair Credit Amortized Fair Japan National Government (1) A+ $52,786 $63,020 A+ $51,726 $62,584 (1) Japan Government Bonds (JGBs) or JGB-backed securities
Gain (Loss) on Investments	Information regarding pretax net gains and losses from investments is as follows: Three Months Ended (In millions) 2020 2019 Net investment gains (losses): Sales and redemptions: Fixed maturity securities available for sale: Gross gains from sales $ 7 $ 12 Gross losses from sales 0 (8 ) Foreign currency gains (losses) on sales and redemptions (14 ) 13 Total sales and redemptions (7 ) 17 Equity securities (149 ) 58 Loan loss reserves (1) 0 (2 ) Credit losses: Fixed maturity securities available for sale (63 ) 0 Fixed maturity securities held to maturity 1 0 Commercial mortgage and other loans (37 ) 0 Loan commitments (46 ) 0 Total credit losses (145 ) 0 Derivatives and other: Derivative gains (losses) (85 ) 0 Foreign currency gains (losses) (77 ) (2 ) Total derivatives and other (162 ) (2 ) Total net investment gains (losses) $ (463 ) $ 71 (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities	The net effect on shareholders’ equity of unrealized gains and losses from fixed maturity securities was as follows: (In millions) March 31, 2020 December 31, Unrealized gains (losses) on securities available for sale $ 8,470 $ 11,891 Deferred income taxes (2,427 ) (3,343 ) Shareholders’ equity, unrealized gains (losses) on fixed maturity securities $ 6,043 $ 8,548
Investments Gross Unrealized Loss Aging	The following tables show the fair values and gross unrealized losses of the Company's available-for-sale investments for the periods ended March 31, 2020 and available-for-sale and held-to-maturity investments for prior periods that were in an unrealized loss position, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position. March 31, 2020 Total Less than 12 months 12 months or longer (In millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed maturity securities available Japan government and Yen-denominated $ 725 $ 14 $ 725 $ 14 $ 0 $ 0 Municipalities: Yen-denominated 56 1 42 0 14 1 Public utilities: U.S. dollar-denominated 825 50 701 38 124 12 Yen-denominated 880 93 880 93 0 0 Sovereign and supranational: U.S. dollar-denominated 18 1 18 1 0 0 Yen-denominated 701 27 701 27 0 0 Banks/financial institutions: U.S. dollar-denominated 355 21 321 13 34 8 Yen-denominated 3,410 557 2,626 406 784 151 Other corporate: U.S. dollar-denominated 8,244 988 5,427 527 2,817 461 Yen-denominated 2,829 389 2,677 357 152 32 Total $ 18,043 $ 2,141 $ 14,118 $ 1,476 $ 3,925 $ 665 December 31, 2019 Total Less than 12 months 12 months or longer (In millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed maturity securities: Municipalities: Yen-denominated $ 80 $ 3 $ 80 $ 3 $ 0 $ 0 Public utilities: U.S. dollar-denominated 306 10 69 2 237 8 Banks/financial institutions: U.S. dollar-denominated 79 4 18 0 61 4 Yen-denominated 1,828 89 1,828 89 0 0 Other corporate: U.S. dollar-denominated 4,261 248 792 53 3,469 195 Yen-denominated 636 31 636 31 0 0 Total $ 7,190 $ 385 $ 3,423 $ 178 $ 3,767 $ 207
Composition of the Carrying Value for Commercial Mortgage and Other Loans by Property Type	The following table reflects the composition of the carrying value for commercial mortgage and other loans by property type as of the periods presented. (In millions) March 31, 2020 December 31, 2019 Amortized Cost % of Total Amortized Cost % of Total Commercial Mortgage and other loans: Transitional real estate loans: Office $ 1,954 18.0 % $ 1,800 18.7 % Retail 165 1.5 131 1.4 Apartments/Multi-Family 2,065 19.0 2,085 21.7 Industrial 175 1.6 256 2.7 Hospitality 1,024 9.4 1,036 10.8 Other 260 2.4 164 1.7 Total transitional real estate loans 5,643 51.9 5,472 57.0 Commercial mortgage loans: Office 408 3.8 410 4.3 Retail 346 3.1 348 3.5 Apartments/Multi-Family 589 5.4 569 5.9 Industrial 397 3.7 383 4.0 Total commercial mortgage loans 1,740 16.0 1,710 17.7 Middle market loans 3,492 32.1 2,432 25.3 Total commercial mortgage and other loans $ 10,875 100.0 % $ 9,614 100.0 % Allowance for credit losses (125 ) (45 ) (1) Total net commercial mortgage and other loans $ 10,750 $ 9,569 (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
Allowance for Loan Losses by Portfolio Segment	The following table presents the roll forward of the allowance for credit losses by portfolio segment during the three-month period ended March 31, 2020 . (in millions) Transitional Real Estate Loans Commercial Mortgage Loans Middle Market Loans Held to Maturity Securities Available for Sale Securities Reinsurance Recoverables Balance at December 31, 2019 (1) $ (22 ) $ (3 ) $ (20 ) $ 0 $ 0 $ 0 Transition impact to retained earnings (2 ) (8 ) (33 ) (10 ) 0 (11 ) (Addition to) release of allowance for credit losses (3 ) 0 (34 ) 1 (63 ) 0 Balance at March 31, 2020 $ (27 ) $ (11 ) $ (87 ) $ (9 ) $ (63 ) $ (11 ) (1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
Other Investments	The table below reflects the composition of the carrying value for other investments as of the periods presented. (In millions) March 31, 2020 December 31, 2019 Other investments: Policy loans $ 253 $ 250 Short-term investments (1) 892 628 Limited partnerships 669 569 Other 29 30 Total other investments $ 1,843 $ 1,477 (1) Includes securities lending collateral
Securities Lending Transactions Accounted for as Secured Borrowings	Details of collateral by loaned security type and remaining maturity of the agreements were as follows: Securities Lending Transactions Accounted for as Secured Borrowings Remaining Contractual Maturity of the Agreements March 31, 2020 December 31, 2019 (In millions) Overnight (1) Up to 30 Total Overnight (1) Up to 30 Total Securities lending transactions: Fixed maturity securities: Japan government and agencies $ 0 $ 2,318 $ 2,318 $ 0 $ 1,013 $ 1,013 Public utilities 35 0 35 35 0 35 Sovereign and supranational 1 0 1 2 0 2 Banks/financial institutions 68 0 68 48 0 48 Other corporate 547 0 547 778 0 778 Total borrowings $ 651 $ 2,318 $ 2,969 $ 863 $ 1,013 $ 1,876 Gross amount of recognized liabilities for securities lending $ 2,969 $ 1,876 (1) The related loaned security, under the Company's U.S. securities lending program, can be returned to the Company at the transferee's discretion; therefore, they are classified as Overnight and Continuous.
Variable Interest Entity, Consolidated
Investments in Variable Interest Entities	VIEs - Consolidated The following table presents the cost or amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported. Investments in Consolidated Variable Interest Entities March 31, 2020 December 31, 2019 (In millions) Amortized (1) Fair Amortized Fair Assets: Fixed maturity securities, available for sale $ 3,208 $ 3,786 $ 3,308 $ 4,312 Commercial mortgage and other loans 9,051 8,737 7,956 8,015 Other investments (2) 550 550 494 494 Other assets (3) 89 89 169 169 Total assets of consolidated VIEs $ 12,898 $ 13,162 $ 11,927 $ 12,990 Liabilities: Other liabilities (3) $ 235 $ 235 $ 126 $ 126 Total liabilities of consolidated VIEs $ 235 $ 235 $ 126 $ 126 (1) Net of allowance for credit losses (2) Consists entirely of alternative investments in limited partnerships (3) Consists entirely of derivatives
Variable Interest Entity, Not Consolidated
Investments in Variable Interest Entities	VIEs - Not Consolidated The table below reflects the amortized cost, fair value and balance sheet caption in which the Company's investment in VIEs not consolidated are reported. Investments in Variable Interest Entities Not Consolidated March 31, 2020 December 31, 2019 (In millions) Amortized Fair Amortized Fair Assets: Fixed maturity securities, available for sale $ 5,999 $ 6,397 $ 4,129 $ 4,884 Fixed maturity securities, held to maturity 0 0 1,848 2,236 Other investments (1) 119 119 75 74 Total investments in VIEs not consolidated $ 6,118 $ 6,516 $ 6,052 $ 7,194 (1) Consists entirely of alternative investments in limited partnerships
Transitional real estate loans
Financing Receivable Credit Quality Indicators	Transitional Real Estate Loans (In millions) 2020 2019 2018 2017 2016 Prior Total Loan-to-Value Ratio: 0%-59.99% $ 33 $ 471 $ 409 $ 155 $ 20 $ 57 $ 1,145 60%-69.99% 190 777 834 436 0 0 2,237 70%-79.99% 81 858 997 250 14 0 2,200 80% or greater 25 36 0 0 0 0 61 Total $ 329 $ 2,142 $ 2,240 $ 841 $ 34 $ 57 $ 5,643
Commercial mortgage loans
Financing Receivable Credit Quality Indicators	Commercial Mortgage Loans (In millions) 2020 2019 2018 2017 2016 Prior Total Weighted-Average DSCR Loan-to-Value Ratio: 0%-59.99% $ 12 $ 474 $ 156 $ 69 $ 683 $ 0 $ 1,394 2.43 60%-69.99% 27 190 16 0 90 0 323 1.74 70%-79.99% 0 0 0 0 23 0 23 1.32 Total 39 664 172 69 796 0 1,740 2.29 Weighted Average DSCR 1.84 2.33 2.16 2.37 2.30 0 2.29
Middle market loans
Financing Receivable Credit Quality Indicators	Middle Market Loans (In millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Credit Ratings: BBB $ 9 $ 57 $ 52 $ 22 $ 12 $ 0 $ 15 $ 167 BB 86 277 187 140 56 20 84 850 B 210 827 466 309 98 58 338 2,306 CCC 0 58 10 34 25 4 15 146 CC 0 1 0 18 0 2 2 23 Total $ 305 $ 1,220 $ 715 $ 523 $ 191 $ 84 $ 454 $ 3,492

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	March 31, 2020 December 31, 2019 (In millions) Asset Liability Asset Liability Hedge Designation/ Derivative Notional Fair Value Fair Value Notional Fair Value Fair Value Cash flow hedges: Foreign currency swaps - VIE $ 75 $ 0 $ 11 $ 75 $ 0 $ 8 Total cash flow hedges 75 0 11 75 0 8 Fair value hedges: Foreign currency forwards 63 0 1 964 0 38 Foreign currency options 8,809 12 23 11,573 0 5 Interest rate swaptions 243 0 0 243 0 0 Total fair value hedges 9,115 12 24 12,780 0 43 Net investment hedge: Foreign currency forwards 4,985 85 6 4,952 72 2 Foreign currency options 2,040 7 0 2,000 0 0 Total net investment hedge 7,025 92 6 6,952 72 2 Non-qualifying strategies: Foreign currency swaps 2,250 66 38 2,800 72 78 Foreign currency swaps - VIE 2,587 89 224 2,587 169 118 Foreign currency forwards 20,614 184 420 19,821 166 337 Foreign currency options 9,248 8 0 9,553 0 0 Interest rate swaps 2,370 21 0 7,120 3 0 Interest rate swaptions 7 0 0 7 0 0 Total non-qualifying strategies 37,076 368 682 41,888 410 533 Total derivatives $ 53,291 $ 472 $ 723 $ 61,695 $ 482 $ 586
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The following table presents the gains and losses on derivatives and the related hedged items in fair value hedges. Fair Value Hedging Relationships (In millions) Hedging Derivatives Hedged Items Hedging Derivatives Hedged Items Total Gains (Losses) (1) Gains (Losses) (2) Gains (Losses) (2) Net Investment Gains (Losses) Recognized for Fair Value Hedge Three Months Ended March 31, 2020: Foreign currency Fixed maturity securities $ (16 ) $ (7 ) $ (9 ) $ 10 $ 1 Total gains (losses) $ (16 ) $ (7 ) $ (9 ) $ 10 $ 1 Three Months Ended March 31, 2019: Foreign currency forwards Fixed maturity securities $ 9 $ (10 ) $ 19 $ (18 ) $ 1 Foreign currency options Fixed maturity securities (4 ) (4 ) 0 0 0 Interest rate Fixed maturity securities (1 ) (1 ) 0 0 0 Total gains (losses) $ 4 $ (15 ) $ 19 $ (18 ) $ 1 (1) Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss). (2) Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the three -month periods ended March 31, 2020 and 2019, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial.
Schedule of Interest Rate Fair Value Hedges Hedged Items	The following table shows the carrying amounts of assets designated and qualifying as hedged items in fair value hedges of interest rate risk and the related cumulative hedge adjustment included in the carrying amount. (In millions) Carrying Amount of the Hedged Assets/(Liabilities) (1) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities) March 31, 2020 December 31, 2019 March 31, 2020 December 31, 2019 Fixed maturity securities $ 4,469 $ 4,633 $ 249 $ 256 (1) The balance includes hedging adjustment on discontinued hedging relationships of $249 in 2020 and $256 in 2019. The total notional amount of the Company's interest rate swaptions was $243 in 2020 and $243 in 2019. The hedging adjustment related to these derivatives was immaterial.
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance	The following table summarizes the impact to net investment gains (losses) and other comprehensive income (loss) from all derivatives and hedging instruments. Three Months Ended March 31, 2020 2019 (In millions) Net Investment Income (1) Net Investment Other (2) Net Investment Income (1) Net Investment Other (2) Qualifying hedges: Cash flow hedges: Foreign currency swaps - VIE $ (1 ) $ 0 $ (4 ) $ (1 ) $ 0 $ (2 ) Total cash flow hedges (1 ) 0 (3 ) (4 ) (1 ) 0 (3 ) (2 ) Fair value hedges: Foreign currency forwards (3) (6 ) (9 ) Foreign currency options (3) 0 (4 ) Interest rate swaptions (3) 0 0 0 0 0 (1 ) Total fair value hedges 0 (6 ) 0 0 (13 ) (1 ) Net investment hedge: Non-derivative hedging instruments 0 6 0 0 Foreign currency forwards 51 (25 ) 0 0 Foreign currency options 6 0 0 0 Total net investment hedge 57 (19 ) 0 0 Non-qualifying strategies: Foreign currency swaps 50 44 Foreign currency swaps - VIE (195 ) (16 ) Foreign currency forwards (36 ) (21 ) Foreign currency options (2 ) 0 Interest rate swaps 47 6 Total non-qualifying strategies (136 ) 13 Total $ (1 ) $ (85 ) $ (23 ) $ (1 ) $ 0 $ (3 ) (1) Cash flow hedge items and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses) on derivatives and net investment hedge items are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss). (2) Impact of cash flow hedges reported as net investment gains (losses) includes an immaterial amount of gains or losses reclassified from accumulated other comprehensive income (loss) into earnings. It also includes an immaterial amount excluded from effectiveness testing during the three -month periods ended March 31, 2020 and 2019 , respectively. (3) Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail)
Offsetting Assets	Offsetting of Financial Assets and Derivative Assets March 31, 2020 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Assets Gross Amount Offset in Balance Sheet Net Amount of Assets Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Received Net Amount Derivative assets: Derivative assets subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 362 $ 0 $ 362 $ (229 ) $ (7 ) $ (121 ) $ 5 OTC - cleared 21 0 21 0 0 (11 ) 10 Total derivative assets subject to a master netting agreement or offsetting arrangement 383 0 383 (229 ) (7 ) (132 ) 15 Derivative assets not subject to a master netting agreement or offsetting arrangement OTC - bilateral 89 89 89 Total derivative assets not subject to a master netting agreement or offsetting arrangement 89 89 89 Total derivative assets 472 0 472 (229 ) (7 ) (132 ) 104 Securities lending and similar arrangements 2,952 0 2,952 0 0 (2,952 ) 0 Total $ 3,424 $ 0 $ 3,424 $ (229 ) $ (7 ) $ (3,084 ) $ 104 December 31, 2019 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Assets Gross Amount Offset in Balance Sheet Net Amount of Assets Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Received Net Amount Derivative assets: Derivative assets subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 310 $ 0 $ 310 $ (190 ) $ (7 ) $ (113 ) $ 0 OTC - cleared 3 0 3 0 0 0 3 Total derivative assets subject to a master netting agreement or offsetting arrangement 313 0 313 (190 ) (7 ) (113 ) 3 Derivative assets not subject to a master netting agreement or offsetting arrangement OTC - bilateral 169 169 169 Total derivative assets not subject to a master netting agreement or offsetting arrangement 169 169 169 Total derivative assets 482 0 482 (190 ) (7 ) (113 ) 172 Securities lending and similar arrangements 1,860 0 1,860 0 0 (1,860 ) 0 Total $ 2,342 $ 0 $ 2,342 $ (190 ) $ (7 ) $ (1,973 ) $ 172
Offsetting Liabilities	Offsetting of Financial Liabilities and Derivative Liabilities March 31, 2020 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Liabilities Gross Amount Offset in Balance Sheet Net Amount of Liabilities Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Pledged Net Amount Derivative liabilities: Derivative liabilities subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 488 $ 0 $ 488 $ (229 ) $ (175 ) $ (2 ) $ 82 Total derivative liabilities subject to a master netting agreement or offsetting arrangement 488 0 488 (229 ) (175 ) (2 ) 82 Derivative liabilities not subject to a master netting agreement or offsetting arrangement OTC - bilateral 235 235 235 Total derivative liabilities not subject to a master netting agreement or offsetting arrangement 235 235 235 Total derivative liabilities 723 0 723 (229 ) (175 ) (2 ) 317 Securities lending and similar arrangements 2,969 0 2,969 (2,952 ) 0 0 17 Total $ 3,692 $ 0 $ 3,692 $ (3,181 ) $ (175 ) $ (2 ) $ 334 December 31, 2019 Gross Amounts Not Offset (In millions) Gross Amount of Recognized Liabilities Gross Amount Offset in Balance Sheet Net Amount of Liabilities Presented in Balance Sheet Financial Instruments Securities Collateral Cash Collateral Pledged Net Amount Derivative liabilities: Derivative liabilities subject to a master netting agreement or offsetting arrangement OTC - bilateral $ 459 $ 0 $ 459 $ (190 ) $ (222 ) $ (32 ) $ 15 OTC - cleared 1 0 1 0 0 (1 ) 0 Total derivative liabilities subject to a master netting agreement or offsetting arrangement 460 0 460 (190 ) (222 ) (33 ) 15 Derivative liabilities not subject to a master netting agreement or offsetting arrangement OTC - bilateral 126 126 126 Total derivative liabilities not subject to a master netting agreement or offsetting arrangement 126 126 126 Total derivative liabilities 586 0 586 (190 ) (222 ) (33 ) 141 Securities lending and similar arrangements 1,876 0 1,876 (1,860 ) 0 0 16 Total $ 2,462 $ 0 $ 2,462 $ (2,050 ) $ (222 ) $ (33 ) $ 157

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Hierarchy, Assets and Liabilities Measured on Recurring Basis	The following tables present the fair value hierarchy levels of the Company's assets and liabilities that are measured and carried at fair value on a recurring basis. March 31, 2020 (In millions) Quoted Prices in Significant Significant Total Assets: Securities available for sale, carried at Fixed maturity securities: Government and agencies $ 35,469 $ 1,509 $ 0 $ 36,978 Municipalities 0 2,440 0 2,440 Mortgage- and asset-backed securities 0 309 188 497 Public utilities 0 8,894 298 9,192 Sovereign and supranational 0 1,609 0 1,609 Banks/financial institutions 0 10,355 23 10,378 Other corporate 0 34,949 245 35,194 Total fixed maturity securities 35,469 60,065 754 96,288 Equity securities 509 69 82 660 Other investments 892 0 0 892 Cash and cash equivalents 4,148 0 0 4,148 Other assets: Foreign currency swaps 0 66 89 155 Foreign currency forwards 0 269 0 269 Foreign currency options 0 27 0 27 Interest rate swaps 0 21 0 21 Total other assets 0 383 89 472 Total assets $ 41,018 $ 60,517 $ 925 $ 102,460 Liabilities: Other liabilities: Foreign currency swaps $ 0 $ 38 $ 235 $ 273 Foreign currency forwards 0 427 0 427 Foreign currency options 0 23 0 23 Total liabilities $ 0 $ 488 $ 235 $ 723 December 31, 2019 (In millions) Quoted Prices in Significant Significant Total Assets: Securities available for sale, carried at Fixed maturity securities: Government and agencies $ 34,878 $ 1,522 $ 0 $ 36,400 Municipalities 0 1,847 0 1,847 Mortgage- and asset-backed securities 0 232 178 410 Public utilities 0 6,556 224 6,780 Sovereign and supranational 0 1,042 0 1,042 Banks/financial institutions 0 10,264 23 10,287 Other corporate 0 34,234 262 34,496 Total fixed maturity securities 34,878 55,697 687 91,262 Equity securities 642 80 80 802 Other investments 628 0 0 628 Cash and cash equivalents 4,896 0 0 4,896 Other assets: Foreign currency swaps 0 72 169 241 Foreign currency forwards 0 238 0 238 Interest rate swaps 0 3 0 3 Total other assets 0 313 169 482 Total assets $ 41,044 $ 56,090 $ 936 $ 98,070 Liabilities: Other liabilities: Foreign currency swaps $ 0 $ 78 $ 126 $ 204 Foreign currency forwards 0 377 0 377 Foreign currency options 0 5 0 5 Total liabilities $ 0 $ 460 $ 126 $ 586
Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost	The following tables present the carrying amount and fair value categorized by fair value hierarchy level for the Company's financial instruments that are not carried at fair value. March 31, 2020 (In millions) Carrying Quoted Prices in Significant Significant Total Assets: Securities held to maturity, Fixed maturity securities: Government and agencies $ 22,384 $ 27,842 $ 352 $ 0 $ 28,194 Municipalities 362 0 484 0 484 Public utilities 45 0 59 0 59 Sovereign and 464 0 578 0 578 Other corporate 23 0 32 0 32 Commercial mortgage and 10,750 0 0 10,390 10,390 Other investments (1) 29 0 29 0 29 Total assets $ 34,057 $ 27,842 $ 1,534 $ 10,390 $ 39,766 Liabilities: Other policyholders’ funds $ 7,422 $ 0 $ 0 $ 7,338 $ 7,338 Notes payable 6,597 0 6,607 274 6,881 Total liabilities $ 14,019 $ 0 $ 6,607 $ 7,612 $ 14,219 (1) Excludes policy loans of $253 and equity method investments of $669 , at carrying value December 31, 2019 (In millions) Carrying Quoted Prices in Significant Significant Total Assets: Securities held to maturity, Fixed maturity securities: Government and agencies $ 22,241 $ 27,937 $ 354 $ 0 $ 28,291 Municipalities 821 0 1,083 0 1,083 Mortgage and asset-backed 16 0 7 10 17 Public utilities 2,535 0 2,954 0 2,954 Sovereign and 1,123 0 1,320 0 1,320 Banks/financial institutions 916 0 1,018 0 1,018 Other corporate 2,433 0 2,911 0 2,911 Commercial mortgage and 9,569 0 0 9,648 9,648 Other investments (1) 30 0 30 0 30 Total assets $ 39,684 $ 27,937 $ 9,677 $ 9,658 $ 47,272 Liabilities: Other policyholders’ funds $ 7,317 $ 0 $ 0 $ 7,234 $ 7,234 Notes payable 6,408 0 6,663 272 6,935 Total liabilities $ 13,725 $ 0 $ 6,663 $ 7,506 $ 14,169 (1) Excludes policy loans of $250 and equity method investments of $569 , at carrying value
Fair Value Assets Securities Carried At Fair Value Primary Pricing Sources	The following tables present the pricing sources for the fair values of the Company's fixed maturity and equity securities. March 31, 2020 (In millions) Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Total Securities available for sale, carried at fair value: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 35,469 $ 1,509 $ 0 $ 36,978 Total government and agencies 35,469 1,509 0 36,978 Municipalities: Third party pricing vendor 0 2,440 0 2,440 Total municipalities 0 2,440 0 2,440 Mortgage- and asset-backed securities: Third party pricing vendor 0 309 0 309 Broker/other 0 0 188 188 Total mortgage- and asset-backed securities 0 309 188 497 Public utilities: Third party pricing vendor 0 8,894 0 8,894 Broker/other 0 0 298 298 Total public utilities 0 8,894 298 9,192 Sovereign and supranational: Third party pricing vendor 0 1,609 0 1,609 Total sovereign and supranational 0 1,609 0 1,609 Banks/financial institutions: Third party pricing vendor 0 10,355 0 10,355 Broker/other 0 0 23 23 Total banks/financial institutions 0 10,355 23 10,378 Other corporate: Third party pricing vendor 0 34,949 0 34,949 Broker/other 0 0 245 245 Total other corporate 0 34,949 245 35,194 Total securities available for sale $ 35,469 $ 60,065 $ 754 $ 96,288 Equity securities, carried at fair value: Third party pricing vendor $ 509 $ 69 $ 0 $ 578 Broker/other 0 0 82 82 Total equity securities $ 509 $ 69 $ 82 $ 660 December 31, 2019 (In millions) Quoted Prices in Active Markets Significant Observable Significant Unobservable Inputs Total Securities available for sale, carried at fair value: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 34,878 $ 1,522 $ 0 $ 36,400 Total government and agencies 34,878 1,522 0 36,400 Municipalities: Third party pricing vendor 0 1,847 0 1,847 Total municipalities 0 1,847 0 1,847 Mortgage- and asset-backed securities: Third party pricing vendor 0 232 0 232 Broker/other 0 0 178 178 Total mortgage- and asset-backed securities 0 232 178 410 Public utilities: Third party pricing vendor 0 6,556 0 6,556 Broker/other 0 0 224 224 Total public utilities 0 6,556 224 6,780 Sovereign and supranational: Third party pricing vendor 0 1,042 0 1,042 Total sovereign and supranational 0 1,042 0 1,042 Banks/financial institutions: Third party pricing vendor 0 10,264 0 10,264 Broker/other 0 0 23 23 Total banks/financial institutions 0 10,264 23 10,287 Other corporate: Third party pricing vendor 0 34,234 0 34,234 Broker/other 0 0 262 262 Total other corporate 0 34,234 262 34,496 Total securities available for sale $ 34,878 $ 55,697 $ 687 $ 91,262 Equity securities, carried at fair value: Third party pricing vendor $ 642 $ 80 $ 0 $ 722 Broker/other 0 0 80 80 Total equity securities $ 642 $ 80 $ 80 $ 802
Fair Value Assets Held-To-Maturity Securities Primary Pricing Sources	March 31, 2020 (In millions) Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Total Securities held to maturity, carried at amortized cost: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 27,842 $ 352 $ 0 $ 28,194 Total government and agencies 27,842 352 0 28,194 Municipalities: Third party pricing vendor 0 484 0 484 Total municipalities 0 484 0 484 Public utilities: Third party pricing vendor 0 59 0 59 Total public utilities 0 59 0 59 Sovereign and supranational: Third party pricing vendor 0 578 0 578 Total sovereign and supranational 0 578 0 578 Other corporate: Third party pricing vendor 0 32 0 32 Total other corporate 0 32 0 32 Total securities held to maturity $ 27,842 $ 1,505 $ 0 $ 29,347 December 31, 2019 (In millions) Quoted Prices in Active Markets Significant Observable Significant Unobservable Inputs Total Securities held to maturity, carried at amortized cost: Fixed maturity securities: Government and agencies: Third party pricing vendor $ 27,937 $ 354 $ 0 $ 28,291 Total government and agencies 27,937 354 0 28,291 Municipalities: Third party pricing vendor 0 1,083 0 1,083 Total municipalities 0 1,083 0 1,083 Mortgage- and asset-backed securities: Third party pricing vendor 0 7 0 7 Broker/other 0 0 10 10 Total mortgage- and asset-backed securities 0 7 10 17 Public utilities: Third party pricing vendor 0 2,954 0 2,954 Total public utilities 0 2,954 0 2,954 Sovereign and supranational: Third party pricing vendor 0 1,320 0 1,320 Total sovereign and supranational 0 1,320 0 1,320 Banks/financial institutions: Third party pricing vendor 0 1,018 0 1,018 Total banks/financial institutions 0 1,018 0 1,018 Other corporate: Third party pricing vendor 0 2,911 0 2,911 Total other corporate 0 2,911 0 2,911 Total securities held to maturity $ 27,937 $ 9,647 $ 10 $ 37,594
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following tables present the changes in fair value of the Company's investments and derivatives carried at fair value classified as Level 3. Three Months Ended Fixed Maturity Securities Equity Derivatives (1) (In millions) Mortgage- Public Banks/ Other Foreign Credit Total Balance, beginning of period $ 178 $ 224 $ 23 $ 262 $ 80 $ 43 $ 0 $ 810 Net investment gains (losses) included 0 0 0 0 0 (185 ) 0 (185 ) Unrealized gains (losses) included in other 1 (8 ) 0 (17 ) 0 (4 ) 0 (28 ) Purchases, issuances, sales and settlements: Purchases 0 83 0 0 2 0 0 85 Issuances 0 0 0 0 0 0 0 0 Sales 0 0 0 0 0 0 0 0 Settlements 0 (1 ) 0 0 0 0 0 (1 ) Transfers into Level 3 9 (2) 0 0 0 0 0 0 9 Transfers out of Level 3 0 0 0 0 0 0 0 0 Balance, end of period $ 188 $ 298 $ 23 $ 245 $ 82 $ (146 ) $ 0 $ 690 Changes in unrealized gains (losses) relating $ 0 $ 0 $ 0 $ 0 $ 0 $ (185 ) $ 0 $ (185 ) (1) Derivative assets and liabilities are presented net (2) Transfer due to reclassification of level 3 securities from HTM to AFS Three Months Ended Fixed Maturity Securities Equity Derivatives (1) (In millions) Mortgage- Public Banks/ Other Foreign Credit Total Balance, beginning of period $ 177 $ 109 $ 23 $ 213 $ 46 $ 80 $ 0 $ 648 Net investment gains (losses) included in earnings 0 0 0 0 0 (8 ) 0 (8 ) Unrealized gains (losses) included in other comprehensive income (loss) 1 1 0 1 0 (2 ) 0 1 Purchases, issuances, sales and settlements: Purchases 0 0 0 63 0 0 0 63 Issuances 0 0 0 0 0 0 0 0 Sales 0 0 0 (2 ) 0 0 0 (2 ) Settlements 0 0 0 0 0 0 0 0 Transfers into Level 3 0 0 0 25 (2) 0 0 0 25 Transfers out of Level 3 0 (25 ) (2) 0 (16 ) (3) 0 0 0 (41 ) Balance, end of period $ 178 $ 85 $ 23 $ 284 $ 46 $ 70 $ 0 $ 686 Changes in unrealized gains (losses) relating $ 0 $ 0 $ 0 $ 0 $ 0 $ (8 ) $ 0 $ (8 ) (1) Derivative assets and liabilities are presented net (2) Transfer due to sector classification change (3) Transfer due to availability of observable market inputs
Fair Value Measurement Inputs and Valuation Techniques	Level 3 Significant Unobservable Input Sensitivity The following tables summarize the significant unobservable inputs used in the valuation of the Company's Level 3 investments and derivatives carried at fair value. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments. March 31, 2020 (In millions) Fair Value Valuation Technique(s) Unobservable Input Range Assets: Securities available for sale, carried at fair value: Fixed maturity securities: Mortgage- and asset-backed securities $ 188 Consensus pricing Offered quotes N/A (a) Public utilities 298 Discounted cash flow Credit spreads N/A (a) Banks/financial institutions 23 Consensus pricing Offered quotes N/A (a) Other corporate 245 Discounted cash flow Credit spreads N/A (a) Equity securities 82 Net asset value Offered quotes N/A (a) Other assets: Foreign currency swaps 15 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) CDS spreads 31 - 173 bps 74 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) Total assets $ 925 Liabilities: Other liabilities: Foreign currency swaps $ 224 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) CDS spreads 31 - 173 bps 11 Discounted cash flow Interest rates (USD) .72% - .88% (b) Interest rates (JPY) .02% - .20% (c) Total liabilities $ 235 (a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs. (b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps (c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps December 31, 2019 (In millions) Fair Value Valuation Technique(s) Unobservable Input Range Assets: Securities available for sale, carried at fair value: Fixed maturity securities: Mortgage- and asset-backed securities $ 178 Consensus pricing Offered quotes N/A (a) Public utilities 224 Discounted cash flow Credit spreads N/A (a) Banks/financial institutions 23 Consensus pricing Offered quotes N/A (a) Other corporate 262 Discounted cash flow Credit spreads N/A (a) Equity securities 80 Net asset value Offered quotes N/A (a) Other assets: Foreign currency swaps 106 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) CDS spreads 10 - 100 bps 63 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) Total assets $ 936 Liabilities: Other liabilities: Foreign currency swaps $ 118 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) CDS spreads 13 - 159 bps 8 Discounted cash flow Interest rates (USD) 1.89% - 2.09% (b) Interest rates (JPY) .12% - .43% (c) Total liabilities $ 126 (a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs. (b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps (c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps

POLICY LIABILITIES (Tables)

POLICY LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2020
Insurance Loss Reserves [Abstract]
Schedule of Liability for Unpaid Claims Adjustment Expense	Changes in the liability for unpaid policy claims were as follows: Three Months Ended (In millions) 2020 2019 Unpaid supplemental health claims, beginning of period $ 3,968 $ 3,952 Less reinsurance recoverables 31 29 Net balance, beginning of period 3,937 3,923 Add claims incurred during the period related to: Current year 1,837 1,825 Prior years (136 ) (167 ) Total incurred 1,701 1,658 Less claims paid during the period on claims incurred during: Current year 556 506 Prior years 1,144 1,137 Total paid 1,700 1,643 Effect of foreign exchange rate changes on unpaid claims 12 0 Net balance, end of period 3,950 3,938 Add reinsurance recoverables 33 29 Unpaid supplemental health claims, end of period 3,983 3,967 Unpaid life claims, end of period 710 658 Total liability for unpaid policy claims $ 4,693 $ 4,625

REINSURANCE (Tables)

REINSURANCE (Tables)	3 Months Ended
	Mar. 31, 2020
Reinsurance Disclosures [Abstract]
Effects of Reinsurance	The following table reconciles direct premium income and direct benefits and claims to net amounts after the effect of reinsurance. Three Months Ended (In millions) 2020 2019 Direct premium income $ 4,772 $ 4,776 Ceded to other companies: Ceded Aflac Japan closed blocks (116 ) (121 ) Other (24 ) (15 ) Assumed from other companies: Retrocession activities 49 50 Other 0 1 Net premium income $ 4,681 $ 4,691 Direct benefits and claims $ 3,028 $ 3,041 Ceded benefits and change in reserves for future benefits: Ceded Aflac Japan closed blocks (105 ) (111 ) Eliminations 10 10 Other (25 ) (11 ) Assumed from other companies: Retrocession activities 41 48 Eliminations (10 ) (10 ) Other 0 0 Benefits and claims, net $ 2,939 $ 2,967

NOTES PAYABLE AND LEASE OBLIG_2

NOTES PAYABLE AND LEASE OBLIGATIONS (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	A summary of notes payable and lease obligations follows: (In millions) March 31, 2020 December 31, 2019 4.00% senior notes paid January 2020 $ 0 $ 348 3.625% senior notes due June 2023 698 698 3.625% senior notes due November 2024 747 747 3.25% senior notes due March 2025 448 448 2.875% senior notes due October 2026 298 298 6.90% senior notes due December 2039 220 220 6.45% senior notes due August 2040 254 254 4.00% senior notes due October 2046 393 394 4.750% senior notes due January 2049 541 541 Yen-denominated senior notes and subordinated debentures: .300% senior notes due September 2025 (principal amount ¥ 12.4 billion) 113 0 .932% senior notes due January 2027 (principal amount ¥60.0 billion) 549 545 .500% senior notes due December 2029 (principal amount ¥12.6 billion) 115 114 .550% senior notes due March 2030 (principal ¥ 13.3 billion) 121 0 1.159% senior notes due October 2030 (principal amount ¥29.3 billion) 268 266 .843% senior notes due December 2031 (principal amount ¥9.3 billion) 85 84 .750% senior notes due March 2032 (principal amount ¥20.7 billion) 189 0 1.488% senior notes due October 2033 (principal amount ¥15.2 billion) 139 138 .934% senior notes due December 2034 (principal amount ¥9.8 billion) 89 88 .830% senior notes due March 2035 (principal amount ¥10.6 billion) 97 0 1.750% senior notes due October 2038 (principal amount ¥8.9 billion) 81 81 1.122% senior notes due December 2039 (principal amount ¥6.3 billion) 57 57 2.108% subordinated debentures due October 2047 (principal amount ¥60.0 billion) 547 543 .963% subordinated bonds due April 2049 (principal amount ¥30.0 billion) 274 272 Yen-denominated loans: Variable interest rate loan due September 2026 (.42% in 2020 and 2019, principal amount ¥5.0 billion) 46 45 Variable interest rate loan due September 2029 (.57% in 2020 and 2019, principal amount ¥25.0 billion) 228 227 Finance lease obligations payable through 2026 12 12 Operating lease obligations payable through 2028 149 149 Total notes payable and lease obligations $ 6,758 $ 6,569 Amounts in the table above are reported net of debt issuance costs and issuance premiums or discounts, if applicable, that are being amortized over the life of the notes.
Schedule of Line of Credit Facilities	A summary of the Company's lines of credit as of March 31, 2020 follows: Borrower(s) Type Term Expiration Date Capacity Amount Outstanding Interest Rate on Borrowed Amount Maturity Period Commitment Fee Business Purpose Aflac Incorporated uncommitted bilateral 364 days December 18, 2020 $100 million $0 million The rate quoted by the bank and agreed upon at the time of borrowing Up to 3 months None General corporate purposes Aflac Incorporated unsecured revolving 5 years March 29, 2024, or the date commitments are terminated pursuant to an event of default ¥100.0 billion ¥0.0 billion A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out period No later than .30% to .50%, depending on the Parent Company's debt ratings as of the date of determination General corporate purposes, including a capital contingency plan for the operations of the Parent Company Aflac Incorporated unsecured revolving 5 years November 18, 2024, or the date commitments are terminated pursuant to an event of default $1.0 billion $0.0 billion A rate per annum equal to, at the Company's option, either, (a) LIBOR adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin No later than November 18, 2024 .085% to .225%, depending on the Parent Company's debt ratings as of the date of determination General corporate purposes, including a capital contingency plan for the operations of the Parent Company Aflac Incorporated uncommitted bilateral None specified None specified $50 million $0 million A rate per annum equal to, at the Parent Company's option, either (a) a eurocurrency rate determined by reference to the agent's LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the greater of (i) the prime rate as determined by the agent, and (ii) the sum of 0.50% and the federal funds rate for such day Up to 3 months None General corporate purposes Aflac (1) uncommitted revolving 364 days November 30, 2020 $250 million $82 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes Aflac Incorporated (1) uncommitted revolving 364 days April 2, 2020 (2) ¥50.0 billion ¥0.0 billion Three-month TIBOR plus 70 basis points per annum 3 months None General corporate purposes Aflac Incorporated (1) uncommitted revolving 364 days November 25, 2020 ¥50.0 billion ¥0.0 billion Three-month TIBOR plus 70 basis points per annum 3 months None General corporate purposes Aflac New York (1) uncommitted revolving 364 days March 20, 2021 $25 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes CAIC (1) uncommitted revolving 364 days March 20, 2021 $15 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes Tier One Insurance Company (1) uncommitted revolving 364 days March 20, 2021 $.3 million $0 million USD three-month LIBOR plus 75 basis points per annum 3 months None General corporate purposes (1) Intercompany credit agreement

SHAREHOLDERS' EQUITY (Tables)

SHAREHOLDERS' EQUITY (Tables)	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Schedule of Common Stock Outstanding Roll Forward	The following table is a reconciliation of the number of shares of the Company's common stock for the three -month periods ended March 31 . (In thousands of shares) 2020 2019 Common stock - issued: Balance, beginning of period 1,349,309 1,347,540 Exercise of stock options and issuance of restricted shares 1,341 1,060 Balance, end of period 1,350,650 1,348,600 Treasury stock: Balance, beginning of period 622,516 592,254 Purchases of treasury stock: Share repurchase program 9,984 10,237 Other 508 561 Dispositions of treasury stock: Shares issued to AFL Stock Plan (468 ) (430 ) Exercise of stock options (45 ) (231 ) Other (227 ) (278 ) Balance, end of period 632,268 602,113 Shares outstanding, end of period 718,382 746,487
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following table presents the approximate number of share-based awards to purchase shares, on a weighted-average basis, that were considered to be anti-dilutive and were excluded from the calculation of diluted earnings per share for the following periods. Three Months Ended (In thousands) 2020 2019 Anti-dilutive share-based awards 744 22
Changes in Accumulated Other Comprehensive Income (Loss)	The tables below are reconciliations of accumulated other comprehensive income by component for the following periods. Changes in Accumulated Other Comprehensive Income Three Months Ended (In millions) Unrealized Foreign Unrealized Unrealized Pension Total Balance at December 31, 2019 $ (1,623 ) $ 8,548 $ (33 ) $ (277 ) $ 6,615 Cumulative effect of change 0 848 0 0 848 Balance at January 1, 2020 $ (1,623 ) $ 9,396 $ (33 ) $ (277 ) $ 7,463 Other comprehensive 80 (3,359 ) (2 ) (6 ) (3,287 ) Amounts reclassified from 0 6 0 6 12 Net current-period other 80 (3,353 ) (2 ) 0 (3,275 ) Balance at March 31, 2020 $ (1,543 ) $ 6,043 $ (35 ) $ (277 ) $ 4,188 All amounts in the table above are net of tax. Three Months Ended (In millions) Unrealized Foreign Unrealized Unrealized Pension Liability Adjustment Total Balance at December 31, 2018 $ (1,847 ) $ 4,234 $ (24 ) $ (212 ) $ 2,151 Other comprehensive (1 ) 2,340 (2 ) 3 2,340 Amounts reclassified from 0 (13 ) 0 3 (10 ) Net current-period other (1 ) 2,327 (2 ) 6 2,330 Balance at March 31, 2019 $ (1,848 ) $ 6,561 $ (26 ) $ (206 ) $ 4,481
Reclassification Out Of Accumulated Other Comprehensive Income	The tables below summarize the amounts reclassified from each component of accumulated other comprehensive income into net earnings for the following periods. Reclassifications Out of Accumulated Other Comprehensive Income (In millions) Three Months Ended Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Unrealized gains (losses) on available-for-sale $ (7 ) Net investment gains (losses) 1 Tax (expense) or benefit (1) $ (6 ) Net of tax Amortization of defined benefit pension items: Actuarial gains (losses) $ (8 ) Acquisition and operating expenses (2) Prior service (cost) credit 0 Acquisition and operating expenses (2) 2 Tax (expense) or benefit (1) $ (6 ) Net of tax Total reclassifications for the period $ (12 ) Net of tax (1) Based on 21% blended tax rate (2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 12 for additional details). (In millions) Three Months Ended Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Unrealized gains (losses) on available-for-sale $ 17 Net investment gains (losses) (4 ) Tax (expense) or benefit (1) $ 13 Net of tax Amortization of defined benefit pension items: Actuarial gains (losses) $ (4 ) Acquisition and operating expenses (2) Prior service (cost) credit 0 Acquisition and operating expenses (2) 1 Tax (expense) or benefit (1) $ (3 ) Net of tax Total reclassifications for the period $ 10 Net of tax (1) Based on 25% blended tax rate (2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 12 for additional details).

SHARE-BASED COMPENSATION (Table

SHARE-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock Options Outstanding and Exercisable	The following table provides information on stock options outstanding and exercisable at March 31, 2020 . Stock Weighted-Average Aggregate Weighted-Average Outstanding 3,354 4.4 $ 16 $ 29.98 Exercisable 3,353 4.4 16 29.97
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes restricted stock activity during the three -month period ended March 31, 2020 . (In thousands of shares) Shares Weighted-Average Grant-Date Fair Value Per Share Restricted stock at December 31, 2019 2,573 $ 44.66 Granted in 2020 1,376 46.66 Canceled in 2020 (25 ) 46.52 Vested in 2020 (1,358 ) 38.48 Restricted stock at March 31, 2020 2,566 $ 48.97

BENEFIT PLANS (Tables)

BENEFIT PLANS (Tables)	3 Months Ended
	Mar. 31, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Schedule of Net Benefit Costs	Pension and other postretirement benefit expenses are included in acquisition and operating expenses in the consolidated statement of earnings, which includes other components of net periodic pension cost and postretirement costs (other than service costs) of $6 million and $5 million for the three -month periods ended March 31, 2020 and 2019 , respectively. Total net periodic cost includes the following components: Three Months Ended March 31, Pension Benefits Other Japan U.S. Postretirement Benefits (In millions) 2020 2019 2020 2019 2020 2019 Components of net periodic Service cost $ 6 $ 5 $ 7 $ 6 $ 0 $ 0 Interest cost 1 1 8 9 0 0 Expected return on plan (2 ) (2 ) (9 ) (7 ) 0 0 Amortization of net actuarial 1 1 6 3 1 0 Net periodic (benefit) cost $ 6 $ 5 $ 12 $ 11 $ 1 $ 0

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions, ¥ in Billions		3 Months Ended
		Mar. 31, 2020JPY (¥)	Mar. 31, 2019	Apr. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)
Senior notes
Significant Accounting Policies [Line Items]
Debt instrument, principal amount | ¥		¥ 57
Aflac Japan
Significant Accounting Policies [Line Items]
Percentage of the Company's total assets		84.00%			84.00%		84.00%
Percentage of the Company's total revenues		67.00%	68.00%
Accounting Standards Update 2016-13
Significant Accounting Policies [Line Items]
Cumulative effect of change in accounting principle, net of income taxes	[1]						$ (56)
Accounting Standards Update 2019-04
Significant Accounting Policies [Line Items]
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Reclassification From Held To Maturity To Available For Sale Debt Securities						$ 6,900
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Unrealized Gain Loss Net Of Tax Reclassification To Accumulated Other Comprehensive Income						848
Cumulative effect of change in accounting principle, net of income taxes	[1]						848
Unrealized gains (losses) on investment securities | Accounting Standards Update 2019-04
Significant Accounting Policies [Line Items]
Cumulative effect of change in accounting principle, net of income taxes						848
Retained earnings | Accounting Standards Update 2016-13
Significant Accounting Policies [Line Items]
Cumulative effect of change in accounting principle, net of income taxes						$ (56)	(56)	[1]
Retained earnings | Accounting Standards Update 2019-04
Significant Accounting Policies [Line Items]
Cumulative effect of change in accounting principle, net of income taxes	[1]						$ 0
Subsequent event | 3.60% senior notes due April 2030
Significant Accounting Policies [Line Items]
Debt instrument, principal amount				$ 1,000
100.0 billion yen line of credit
Significant Accounting Policies [Line Items]
Line of credit facility, maximum borrowing capacity | ¥		¥ 100
$1 billion line of credit
Significant Accounting Policies [Line Items]
Line of credit facility, maximum borrowing capacity					$ 1,000
Federal Home Loan Bank of Atlanta
Significant Accounting Policies [Line Items]
Line of credit facility, maximum borrowing capacity					800
Line of credit facility, capacity designated for short-term liquidity					$ 300
[1]	See Note 1 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance on January 1, 2020

BUSINESS SEGMENT INFORMATION -

BUSINESS SEGMENT INFORMATION - Operations by Segment - Revenues (Details) $ in Millions		3 Months Ended
		Mar. 31, 2020USD ($)segment	Mar. 31, 2019USD ($)
Segment Reporting, Revenue Reconciling Item [Line Items]
Number of reportable insurance business segments | segment		2
Net earned premiums		$ 4,681	$ 4,691
Net investment income		904	878
Total adjusted revenues		5,594	5,537
Net investment gains (losses)	[1],[2],[3]	(432)	120
Total revenues		5,162	5,657
Aflac Japan
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums		3,150	3,180
Adjusted net investment income	[1],[3]	642	610
Other income		11	12
Total revenues		3,803	3,802
Hedge costs		55	62
Net interest cash flows from derivatives		(6)	(7)
Aflac U.S.
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums		1,483	1,461
Net investment income		177	177
Other income		27	2
Total revenues		1,687	1,640
Corporate and other
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues	[2]	104	95
Hedge income		$ 29	$ 20
[1]	Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
[2]	Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
[3]	Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income.

BUSINESS SEGMENT INFORMATION _2

BUSINESS SEGMENT INFORMATION - Operations by Segment - Pretax Earnings (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Reconciling Item for Adjusted Profit (Loss) from Segment to Consolidated [Line Items]
Pretax adjusted earnings	[1]	$ 1,183	$ 1,139
Net investment gains (losses)	[2],[3],[4],[5]	(448)	103
Other income (loss)		(15)	0
Earnings before income taxes		720	1,242
Income taxes applicable to pretax adjusted earnings		301	291
Effect of foreign currency translation on after tax adjusted earnings		9	(8)
Interest expense on debt		33	33
Aflac Japan
Segment Reporting, Reconciling Item for Adjusted Profit (Loss) from Segment to Consolidated [Line Items]
Pretax adjusted earnings	[3],[5]	855	834
Hedge costs		55	62
Net interest cash flows from derivatives		(6)	(7)
Aflac U.S.
Segment Reporting, Reconciling Item for Adjusted Profit (Loss) from Segment to Consolidated [Line Items]
Pretax adjusted earnings		326	323
Corporate and other
Segment Reporting, Reconciling Item for Adjusted Profit (Loss) from Segment to Consolidated [Line Items]
Pretax adjusted earnings	[2],[4]	2	(18)
Hedge income		29	20
Gain (loss) on change in fair value of derivative, interest rate component		$ 16	$ 17
[1]	Includes $33 for the three-month periods ended March 31, 2020 , and 2019 , respectively, of interest expense on debt.
[2]	A gain of $16 and $17 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations.
[3]	Amortized hedge costs of $55 and $62 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
[4]	Amortized hedge income of $29 and $20 for the three -month periods ended March 31, 2020 , and 2019 , respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase in net investment income when analyzing operations.
[5]	Net interest cash flows from derivatives associated with certain investment strategies of $(6) and $(7) for the three -month periods ended March 31, 2020 and 2019 , respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income.

BUSINESS SEGMENT INFORMATION _3

BUSINESS SEGMENT INFORMATION - Operations by Segment - Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 151,616	$ 152,768
Aflac Japan
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	126,955	127,523
Aflac U.S.
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	20,526	20,945
Corporate and other
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 4,135	$ 4,300

INVESTMENTS - Available-for-sal

INVESTMENTS - Available-for-sale Debt Securities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 87,881	$ 79,371
Allowance for Credit Losses	63
Gross Unrealized Gains	10,611	12,266
Gross Unrealized Losses	2,141	375
Fair Value	96,288	91,262
Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,831	45,684
Allowance for Credit Losses	0
Gross Unrealized Gains	6,645	7,410
Gross Unrealized Losses	1,081	113
Fair Value	59,395	52,981
Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	34,050	33,687
Allowance for Credit Losses	63
Gross Unrealized Gains	3,966	4,856
Gross Unrealized Losses	1,060	262
Fair Value	36,893	38,281
Japan government and agencies | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	31,853	30,929
Allowance for Credit Losses	0
Gross Unrealized Gains	4,766	5,169
Gross Unrealized Losses	14	0
Fair Value	36,605	36,098
Municipalities
Debt Securities, Available-for-sale [Line Items]
Fair Value	2,440	1,847
Municipalities | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	984	516
Allowance for Credit Losses	0
Gross Unrealized Gains	228	116
Gross Unrealized Losses	1	3
Fair Value	1,211	629
Municipalities | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,084	1,077
Allowance for Credit Losses	0
Gross Unrealized Gains	145	141
Gross Unrealized Losses	0	0
Fair Value	1,229	1,218
Mortgage- and asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	497	410
Mortgage- and asset-backed securities | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	306	229
Allowance for Credit Losses	0
Gross Unrealized Gains	31	25
Gross Unrealized Losses	0	0
Fair Value	337	254
Mortgage- and asset-backed securities | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	152	149
Allowance for Credit Losses	0
Gross Unrealized Gains	8	7
Gross Unrealized Losses	0	0
Fair Value	160	156
Public utilities
Debt Securities, Available-for-sale [Line Items]
Fair Value	9,192	6,780
Public utilities | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,412	1,855
Allowance for Credit Losses	0
Gross Unrealized Gains	430	406
Gross Unrealized Losses	93	0
Fair Value	4,749	2,261
Public utilities | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,844	3,804
Allowance for Credit Losses	0
Gross Unrealized Gains	649	725
Gross Unrealized Losses	50	10
Fair Value	4,443	4,519
Sovereign and supranational
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,609	1,042
Sovereign and supranational | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,300	680
Allowance for Credit Losses	0
Gross Unrealized Gains	33	50
Gross Unrealized Losses	27	0
Fair Value	1,306	730
Sovereign and supranational | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	239	239
Allowance for Credit Losses	0
Gross Unrealized Gains	65	73
Gross Unrealized Losses	1	0
Fair Value	303	312
Banks/financial institutions
Debt Securities, Available-for-sale [Line Items]
Fair Value	10,378	10,287
Banks/financial institutions | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,159	6,152
Allowance for Credit Losses	0
Gross Unrealized Gains	404	700
Gross Unrealized Losses	557	86
Fair Value	7,006	6,766
Banks/financial institutions | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,848	2,879
Allowance for Credit Losses	0
Gross Unrealized Gains	545	646
Gross Unrealized Losses	21	4
Fair Value	3,372	3,521
Other corporate
Debt Securities, Available-for-sale [Line Items]
Fair Value	35,194	34,496
Other corporate | Yen-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,817	5,323
Allowance for Credit Losses	0
Gross Unrealized Gains	753	944
Gross Unrealized Losses	389	24
Fair Value	8,181	6,243
Other corporate | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,533	25,246
Allowance for Credit Losses	63
Gross Unrealized Gains	2,531	3,255
Gross Unrealized Losses	988	248
Fair Value	27,013	28,253
U.S. government and agencies | Dollar-denominated
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	350	293
Allowance for Credit Losses	0
Gross Unrealized Gains	23	9
Gross Unrealized Losses	0	0
Fair Value	$ 373	$ 302

INVESTMENTS - Held-to-Maturity

INVESTMENTS - Held-to-Maturity Debt Securities (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		$ 23,287	$ 30,085
Allowance for Credit Loss		9
Net Carrying Amount	[1]	23,278
Gross Unrealized Gains		6,069	7,519
Gross Unrealized Losses		0	10
Fair Value		29,347	37,594
Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		23,287	30,085
Allowance for Credit Loss		9
Net Carrying Amount		23,278
Gross Unrealized Gains		6,069	7,519
Gross Unrealized Losses		0	10
Fair Value		29,347	37,594
Japan government and agencies | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		22,387	22,241
Allowance for Credit Loss		3
Net Carrying Amount		22,384
Gross Unrealized Gains		5,810	6,050
Gross Unrealized Losses		0	0
Fair Value		28,194	28,291
Municipalities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		362	821
Fair Value		484	1,083
Municipalities | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		362	821
Allowance for Credit Loss		0
Net Carrying Amount		362
Gross Unrealized Gains		122	262
Gross Unrealized Losses		0	0
Fair Value		484	1,083
Mortgage- and asset-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost			16
Fair Value			17
Mortgage- and asset-backed securities | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost			16
Gross Unrealized Gains			1
Gross Unrealized Losses			0
Fair Value			17
Public utilities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		45	2,535
Fair Value		59	2,954
Public utilities | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		46	2,535
Allowance for Credit Loss		1
Net Carrying Amount		45
Gross Unrealized Gains		14	419
Gross Unrealized Losses		0	0
Fair Value		59	2,954
Sovereign and supranational
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		464	1,123
Fair Value		578	1,320
Sovereign and supranational | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		469	1,123
Allowance for Credit Loss		5
Net Carrying Amount		464
Gross Unrealized Gains		114	197
Gross Unrealized Losses		0	0
Fair Value		578	1,320
Banks/financial institutions
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost			916
Fair Value			1,018
Banks/financial institutions | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost			916
Gross Unrealized Gains			105
Gross Unrealized Losses			3
Fair Value			1,018
Other corporate
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		23	2,433
Fair Value		32	2,911
Other corporate | Yen-denominated
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost		23	2,433
Allowance for Credit Loss		0
Net Carrying Amount		23
Gross Unrealized Gains		9	485
Gross Unrealized Losses		0	7
Fair Value		$ 32	$ 2,911
[1]	Net of allowance for credit losses

INVESTMENTS - Equity Securities

INVESTMENTS - Equity Securities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Equity Securities, FV-NI [Line Items]
Fair Value	$ 660	$ 802
Yen-denominated
Equity Securities, FV-NI [Line Items]
Fair Value	528	658
Dollar-denominated
Equity Securities, FV-NI [Line Items]
Fair Value	$ 132	$ 144

INVESTMENTS - Contractual and E

INVESTMENTS - Contractual and Economic Maturities of Investments in Fixed Maturities (Detail) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Available for sale:
Due in one year or less	[1]	$ 1,078
Due after one year through five years	[1]	8,992
Due after five years through 10 years	[1]	12,399
Due after 10 years	[1]	64,891
Mortgage- and asset-backed securities	[1]	458
Total fixed maturity securities, available for sale, amortized cost	[1]	87,818
Held to maturity:
Due in one year or less	[1]	0
Due after one year through five years	[1]	0
Due after five years through 10 years	[1]	49
Due after 10 years	[1]	23,229
Mortgage- and asset-backed securities	[1]	0
Total fixed maturity securities, held to maturity, amortized cost	[1]	23,278
Available for sale:
Due in one year or less		1,105
Due after one year through five years		8,806
Due after five years through 10 years		13,221
Due after 10 years		72,659
Mortgage- and asset-backed securities		497
Total fixed maturity securities, available for sale, fair value		96,288	$ 91,262
Held to maturity:
Due in one year or less		0
Due after one year through five years		0
Due after five years through 10 years		55
Due after 10 years		29,292
Mortgage- and asset-backed securities		0
Total fixed maturity securities, held to maturity, fair value		$ 29,347	$ 37,594
[1]	Net of allowance for credit losses

INVESTMENTS - Investment Exposu

INVESTMENTS - Investment Exposures Individually Exceeded 10% of Shareholders' Equity (Details) - Japan National Government - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2020	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Credit Rating	[1]	A+	A+
Amortized Cost	[1]	$ 52,786	$ 51,726
Fair Value	[1]	$ 63,020	$ 62,584
[1]	Japan Government Bonds (JGBs) or JGB-backed securities

INVESTMENTS - Information Regar

INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Gain (Loss) on Securities [Line Items]
Loan loss reserves	[1]	$ 0	$ (2)
Credit Losses
Fixed maturity securities available for sale		(63)	0
Fixed maturity securities held to maturity		1	0
Commercial mortgage and other loans		(37)	0
Loan commitments		(46)	0
Total credit losses		(145)	0
Total net investment gains (losses)		(463)	71
Derivatives and Other
Derivative gains (losses)		(85)	0
Foreign currency gains (losses)		(77)	(2)
Derivatives and other
Credit Losses
Total net investment gains (losses)		(162)	(2)
Equity securities
Credit Losses
Total net investment gains (losses)		(149)	58
Available-for-sale securities | Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales		7	12
Gross losses from sales		0	(8)
Foreign currency gains (losses) on sales and redemptions		(14)	13
Credit Losses
Total net investment gains (losses)		$ (7)	$ 17
[1]	U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.

INVESTMENTS - Net Effect on Sha

INVESTMENTS - Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Investments [Abstract]
Unrealized gains (losses) on securities available for sale	$ 8,470	$ 11,891
Deferred income taxes	(2,427)	(3,343)
Shareholders' equity, unrealized gains (losses) on fixed maturity securities	$ 6,043	$ 8,548

INVESTMENTS - Fair Value and Gr

INVESTMENTS - Fair Value and Gross Unrealized Losses for Securities That Have Been in Continuous Unrealized Loss Position (Detail) - Fixed maturity securities - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	$ 18,043	$ 7,190
Total Unrealized Losses	2,141	385
Less than 12 months Fair Value	14,118	3,423
Less than 12 months Unrealized Losses	1,476	178
12 months or longer Fair Value	3,925	3,767
12 months or longer Unrealized Losses	665	207
Yen-denominated | Municipalities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	56	80
Total Unrealized Losses	1	3
Less than 12 months Fair Value	42	80
Less than 12 months Unrealized Losses	0	3
12 months or longer Fair Value	14	0
12 months or longer Unrealized Losses	1	0
Yen-denominated | Public utilities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	880
Total Unrealized Losses	93
Less than 12 months Fair Value	880
Less than 12 months Unrealized Losses	93
12 months or longer Fair Value	0
12 months or longer Unrealized Losses	0
Yen-denominated | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	701
Total Unrealized Losses	27
Less than 12 months Fair Value	701
Less than 12 months Unrealized Losses	27
12 months or longer Fair Value	0
12 months or longer Unrealized Losses	0
Yen-denominated | Banks/financial institutions
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	3,410	1,828
Total Unrealized Losses	557	89
Less than 12 months Fair Value	2,626	1,828
Less than 12 months Unrealized Losses	406	89
12 months or longer Fair Value	784	0
12 months or longer Unrealized Losses	151	0
Yen-denominated | Other corporate
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	2,829	636
Total Unrealized Losses	389	31
Less than 12 months Fair Value	2,677	636
Less than 12 months Unrealized Losses	357	31
12 months or longer Fair Value	152	0
12 months or longer Unrealized Losses	32	0
Yen-denominated | Japan government and agencies
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	725
Total Unrealized Losses	14
Less than 12 months Fair Value	725
Less than 12 months Unrealized Losses	14
12 months or longer Fair Value	0
12 months or longer Unrealized Losses	0
Dollar-denominated | Public utilities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	825	306
Total Unrealized Losses	50	10
Less than 12 months Fair Value	701	69
Less than 12 months Unrealized Losses	38	2
12 months or longer Fair Value	124	237
12 months or longer Unrealized Losses	12	8
Dollar-denominated | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	18
Total Unrealized Losses	1
Less than 12 months Fair Value	18
Less than 12 months Unrealized Losses	1
12 months or longer Fair Value	0
12 months or longer Unrealized Losses	0
Dollar-denominated | Banks/financial institutions
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	355	79
Total Unrealized Losses	21	4
Less than 12 months Fair Value	321	18
Less than 12 months Unrealized Losses	13	0
12 months or longer Fair Value	34	61
12 months or longer Unrealized Losses	8	4
Dollar-denominated | Other corporate
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	8,244	4,261
Total Unrealized Losses	988	248
Less than 12 months Fair Value	5,427	792
Less than 12 months Unrealized Losses	527	53
12 months or longer Fair Value	2,817	3,469
12 months or longer Unrealized Losses	$ 461	$ 195

INVESTMENTS - Commercial Mortga

INVESTMENTS - Commercial Mortgage and Other Loans by Portfolio Segment (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 10,875	$ 9,614
Percent of total commercial mortgage and other loans	100.00%	100.00%
Allowance for credit losses	$ (125)	$ (45)	[1]
Total net commercial mortgage and other loans	10,750	9,569
Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 5,643	$ 5,472
Percent of total commercial mortgage and other loans	51.90%	57.00%
Allowance for credit losses	$ (27)	$ (22)	[1]
Commercial mortgage loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 1,740	$ 1,710
Percent of total commercial mortgage and other loans	16.00%	17.70%
Allowance for credit losses	$ (11)	$ (3)	[1]
Middle market loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 3,492	$ 2,432
Percent of total commercial mortgage and other loans	32.10%	25.30%
Allowance for credit losses	$ (87)	$ (20)	[1]
Office | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 1,954	$ 1,800
Percent of total commercial mortgage and other loans	18.00%	18.70%
Office | Commercial mortgage loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 408	$ 410
Percent of total commercial mortgage and other loans	3.80%	4.30%
Retail | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 165	$ 131
Percent of total commercial mortgage and other loans	1.50%	1.40%
Retail | Commercial mortgage loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 346	$ 348
Percent of total commercial mortgage and other loans	3.10%	3.50%
Apartment/Multi-Family | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 2,065	$ 2,085
Percent of total commercial mortgage and other loans	19.00%	21.70%
Apartment/Multi-Family | Commercial mortgage loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 589	$ 569
Percent of total commercial mortgage and other loans	5.40%	5.90%
Industrial | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 175	$ 256
Percent of total commercial mortgage and other loans	1.60%	2.70%
Industrial | Commercial mortgage loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 397	$ 383
Percent of total commercial mortgage and other loans	3.70%	4.00%
Hospitality | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 1,024	$ 1,036
Percent of total commercial mortgage and other loans	9.40%	10.80%
Other | Transitional real estate loans
Participating Mortgage Loans [Line Items]
Commercial mortgage and other loans, gross	$ 260	$ 164
Percent of total commercial mortgage and other loans	2.40%	1.70%
[1]	U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.

INVESTMENTS - Transitional Real

INVESTMENTS - Transitional Real Estate Loans by Key Credit Quality Indicators (Details) - Transitional real estate loans	Mar. 31, 2020USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 329
2019	2,142
2018	2,240
2017	841
2016	34
Prior	57
Total Financing Receivable	5,643
Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	33
2019	471
2018	409
2017	155
2016	20
Prior	57
Total Financing Receivable	1,145
Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	190
2019	777
2018	834
2017	436
2016	0
Prior	0
Total Financing Receivable	2,237
Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	81
2019	858
2018	997
2017	250
2016	14
Prior	0
Total Financing Receivable	2,200
Loan-to-Value Ratio Eighty Percent and Above
Financing Receivable, Credit Quality Indicator [Line Items]
2020	25
2019	36
2018	0
2017	0
2016	0
Prior	0
Total Financing Receivable	$ 61

INVESTMENTS - Commercial Mort_2

INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicators (Details) - Commercial mortgage loans	Mar. 31, 2020USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 39
2019	664
2018	172
2017	69
2016	796
Prior	0
Total Financing Receivable	$ 1,740
Weighted Average Debt Service Coverage Ratio	2.29
2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	1.84
2019
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.33
2018
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.16
2017
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.37
2016
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.30
Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	0
Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 12
2019	474
2018	156
2017	69
2016	683
Prior	0
Total Financing Receivable	$ 1,394
Weighted Average Debt Service Coverage Ratio	2.43
Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 27
2019	190
2018	16
2017	0
2016	90
Prior	0
Total Financing Receivable	$ 323
Weighted Average Debt Service Coverage Ratio	1.74
Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 0
2019	0
2018	0
2017	0
2016	23
Prior	0
Total Financing Receivable	$ 23
Weighted Average Debt Service Coverage Ratio	1.32

INVESTMENTS - Middle Market Loa

INVESTMENTS - Middle Market Loans by Key Credit Quality Indicators (Details) - Middle market loans	Mar. 31, 2020USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 305
2019	1,220
2018	715
2017	523
2016	191
Prior	84
Revolving Loans	454
Total Financing Receivable	3,492
BBB
Financing Receivable, Credit Quality Indicator [Line Items]
2020	9
2019	57
2018	52
2017	22
2016	12
Prior	0
Revolving Loans	15
Total Financing Receivable	167
BB
Financing Receivable, Credit Quality Indicator [Line Items]
2020	86
2019	277
2018	187
2017	140
2016	56
Prior	20
Revolving Loans	84
Total Financing Receivable	850
B
Financing Receivable, Credit Quality Indicator [Line Items]
2020	210
2019	827
2018	466
2017	309
2016	98
Prior	58
Revolving Loans	338
Total Financing Receivable	2,306
CCC
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	58
2018	10
2017	34
2016	25
Prior	4
Revolving Loans	15
Total Financing Receivable	146
CC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	1
2018	0
2017	18
2016	0
Prior	2
Revolving Loans	2
Total Financing Receivable	$ 23

INVESTMENTS - Allowance for Loa

INVESTMENTS - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	$ (45)
(Addition to) release of allowance for credit losses	[2]	0	$ 2
Balance, end of period		(125)
Transitional real estate loans
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	(22)
Impact of Restatement on Opening Retained Earnings, before Tax				$ 2
(Addition to) release of allowance for credit losses		(3)
Balance, end of period		(27)
Commercial mortgage loans
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	(3)
Impact of Restatement on Opening Retained Earnings, before Tax				8
(Addition to) release of allowance for credit losses		0
Balance, end of period		(11)
Middle market loans
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	(20)
Impact of Restatement on Opening Retained Earnings, before Tax				33
(Addition to) release of allowance for credit losses		(34)
Balance, end of period		(87)
Held-to-maturity securities
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	0
Impact of Restatement on Opening Retained Earnings, before Tax				10
(Addition to) release of allowance for credit losses		1
Balance, end of period		(9)
Available-for-sale securities
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	0
Impact of Restatement on Opening Retained Earnings, before Tax				0
(Addition to) release of allowance for credit losses		(63)
Balance, end of period		(63)
Reinsurance recoverables
Allowance for Loan Losses by Portfolio Segment [Roll Forward]
Balance, beginning of period	[1]	0
Impact of Restatement on Opening Retained Earnings, before Tax				$ 11
(Addition to) release of allowance for credit losses		0
Balance, end of period		$ (11)
[1]	U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
[2]	U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.

INVESTMENTS - Other Investments

INVESTMENTS - Other Investments (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Other investments		$ 1,843	$ 1,477
Policy loans
Investment Holdings [Line Items]
Other investments		253	250
Short-term investments
Investment Holdings [Line Items]
Other investments	[1]	892	628
Limited partnerships
Investment Holdings [Line Items]
Other investments		669	569
Other
Investment Holdings [Line Items]
Other investments		$ 29	$ 30
[1]	Includes securities lending collateral

INVESTMENTS - Investments in Co

INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) - USD ($) $ in Millions		Mar. 31, 2020		Dec. 31, 2019
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		$ 87,881		$ 79,371
Available for sale, fixed maturity securities		96,288		91,262
Equity securities		660		802
Commercial mortgage and other loans		10,750		9,569
Commercial mortgage and other loans, fair value		10,390		9,648
Other investments		1,843		1,477
Asset derivatives		472		482
Assets, fair value		102,460		98,070
Liability derivatives		723		586
Liabilities		125,214		123,809
Liabilities, fair value		723		586
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		3,208	[1]	3,308
Available for sale, fixed maturity securities		3,786		4,312
Commercial mortgage and other loans		9,051		7,956
Commercial mortgage and other loans, fair value		8,737		8,015
Other investments	[2]	550		494
Other investments, fair value	[2]	550		494
Asset derivatives, amortized cost	[3]	89	[1]	169
Asset derivatives	[3]	89		169
Assets, amortized cost		12,898	[1]	11,927
Assets, fair value		13,162		12,990
Liability derivatives, amortized cost	[3]	235	[1]	126
Liability derivatives	[3]	235		126
Liabilities		235	[1]	126
Liabilities, fair value		$ 235		$ 126
[1]	Net of allowance for credit losses
[2]	Consists entirely of alternative investments in limited partnerships
[3]	Consists entirely of derivatives

INVESTMENTS - Investments in Va

INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		$ 87,881	$ 79,371
Available for sale, fixed maturity securities		96,288	91,262
Securities held to maturity, fixed maturities, amortized cost		23,287	30,085
Held to maturity, fixed maturity securities, fair value		29,347	37,594
Other investments		1,843	1,477
Assets, fair value		102,460	98,070
Variable Interest Entity, Not Consolidated
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		5,999	4,129
Available for sale, fixed maturity securities		6,397	4,884
Securities held to maturity, fixed maturities, amortized cost		0	1,848
Held to maturity, fixed maturity securities, fair value		0	2,236
Other investments	[1]	119	75
Other investments, fair value	[1]	119	74
Assets, amortized cost		6,118	6,052
Assets, fair value		$ 6,516	$ 7,194
[1]	Consists entirely of alternative investments in limited partnerships

INVESTMENTS - Securities Lendin

INVESTMENTS - Securities Lending Transactions Accounted for as Secured Borrowings (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		$ 2,969	$ 1,876
Gross amount of recognized liabilities for securities lending		2,969	1,876
Japan government and agencies
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		2,318	1,013
Public utilities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		35	35
Sovereign and supranational
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		1	2
Banks/financial institutions
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		68	48
Other corporate
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		547	778
Maturity Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	651	863
Maturity Overnight and Continuous | Japan government and agencies
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	0	0
Maturity Overnight and Continuous | Public utilities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	35	35
Maturity Overnight and Continuous | Sovereign and supranational
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	1	2
Maturity Overnight and Continuous | Banks/financial institutions
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	68	48
Maturity Overnight and Continuous | Other corporate
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred	[1]	547	778
Maturity up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		2,318	1,013
Maturity up to 30 Days | Japan government and agencies
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		2,318	1,013
Maturity up to 30 Days | Public utilities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		0	0
Maturity up to 30 Days | Sovereign and supranational
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		0	0
Maturity up to 30 Days | Banks/financial institutions
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		0	0
Maturity up to 30 Days | Other corporate
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred		$ 0	$ 0
[1]	The related loaned security, under the Company's U.S. securities lending program, can be returned to the Company at the transferee's discretion; therefore, they are classified as Overnight and Continuous.

INVESTMENTS - Additional Inform

INVESTMENTS - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)	Mar. 31, 2019investment	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)
Schedule of Investments [Line Items]
Held to maturity securities transferred to available for sale securities, number of investments | investment		0
Equity securities, FV-NI, unrealized gain (loss)	$ 149
Available for sale, fixed maturity securities, allowance for credit losses	63
Transitional real estate loan commitments	838
Commercial mortgage loan commitments	10
Middle market loan program unfunded amount	0			$ 99
Middle market loan commitments	2,600
Middle Market Loan Commitment Increase During Period	2,200
Securities held to maturity, fixed maturities, amortized cost	23,287			30,085
Loan Commitments, Allowance for Credit Loss	60
Limited partnerships investment commitments	$ 1,400
Percentage that the lending policy requires that the fair value of the securities received as collateral be of the fair value of the loaned securities	102.00%
Percentage that the lending policy requires that the fair value of the unrestricted cash received as collateral be of the fair value of the loaned securities	100.00%
Securities Lending, Securities Received as Collateral	$ 5,188			4,759
Accounting Standards Update 2019-04
Schedule of Investments [Line Items]
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Reclassification From Held To Maturity To Available For Sale Debt Securities			$ 6,900
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Unrealized Gain Loss Net Of Tax Reclassification To Accumulated Other Comprehensive Income			$ 848
Yen-denominated
Schedule of Investments [Line Items]
Available for sale, fixed maturity securities, allowance for credit losses	0
Securities held to maturity, fixed maturities, amortized cost	23,287			30,085
Japan government and agencies | Yen-denominated
Schedule of Investments [Line Items]
Available for sale, fixed maturity securities, allowance for credit losses	0
Securities held to maturity, fixed maturities, amortized cost	22,387			$ 22,241
Zero-credit-loss expectation | Japan government and agencies | Yen-denominated
Schedule of Investments [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$ 22,000
CALIFORNIA | Commercial Mortgage and Transitional Real Estate Loans
Schedule of Investments [Line Items]
Concentration Risk, Percentage	20.00%
TEXAS | Commercial Mortgage and Transitional Real Estate Loans
Schedule of Investments [Line Items]
Concentration Risk, Percentage	14.00%
FLORIDA | Commercial Mortgage and Transitional Real Estate Loans
Schedule of Investments [Line Items]
Concentration Risk, Percentage	10.00%

DERIVATIVE INSTRUMENTS - Additi

DERIVATIVE INSTRUMENTS - Additional Information (Detail) $ in Millions	Mar. 31, 2020USD ($)yr	Dec. 31, 2019USD ($)
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative, Notional Amount	$ 53,291	$ 61,695
Cash flow hedging activity, maximum time period | yr	7
Derivative, net liability position, aggregate fair value	$ 348	$ 301
Additional Collateral, Aggregate Fair Value	171
Senior notes | Interest rate swaps
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative, Notional Amount	$ 2,300

DERIVATIVE INSTRUMENTS - Summar

DERIVATIVE INSTRUMENTS - Summary of Balance Sheet Classification of Derivative Fair Value Amounts, as well as Gross Asset and Liability Fair Value Amounts (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Notional Amount	$ 53,291	$ 61,695
Derivative asset, fair value, gross asset including not subject to master netting arrangement	472	482
Derivative liability, fair value, gross liability including not subject to master netting arrangement	723	586
Asset derivatives fair value	383	313
Liability derivatives fair value	488	460
Cash flow hedges
Derivatives, Fair Value [Line Items]
Notional Amount	75	75
Asset derivatives fair value	0	0
Liability derivatives fair value	11	8
Cash flow hedges | Foreign currency swaps | Variable Interest Entity
Derivatives, Fair Value [Line Items]
Notional Amount	75	75
Asset derivatives fair value	0	0
Liability derivatives fair value	11	8
Fair value hedges
Derivatives, Fair Value [Line Items]
Notional Amount	9,115	12,780
Asset derivatives fair value	12	0
Liability derivatives fair value	24	43
Fair value hedges | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Notional Amount	63	964
Asset derivatives fair value	0	0
Liability derivatives fair value	1	38
Fair value hedges | Foreign currency options
Derivatives, Fair Value [Line Items]
Notional Amount	8,809	11,573
Asset derivatives fair value	12	0
Liability derivatives fair value	23	5
Fair value hedges | Interest rate swaptions
Derivatives, Fair Value [Line Items]
Notional Amount	243	243
Asset derivatives fair value	0	0
Liability derivatives fair value	0	0
Net investment hedge
Derivatives, Fair Value [Line Items]
Notional Amount	7,025	6,952
Asset derivatives fair value	92	72
Liability derivatives fair value	6	2
Net investment hedge | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Notional Amount	4,985	4,952
Asset derivatives fair value	85	72
Liability derivatives fair value	6	2
Net investment hedge | Foreign currency options
Derivatives, Fair Value [Line Items]
Notional Amount	2,040	2,000
Asset derivatives fair value	7	0
Liability derivatives fair value	0	0
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Notional Amount	37,076	41,888
Asset derivatives fair value	368	410
Liability derivatives fair value	682	533
Non-qualifying strategies | Foreign currency swaps | Variable Interest Entity
Derivatives, Fair Value [Line Items]
Notional Amount	2,587	2,587
Asset derivatives fair value	89	169
Liability derivatives fair value	224	118
Non-qualifying strategies | Foreign currency swaps | Consolidated Entity Excluding Variable Interest Entities (VIE)
Derivatives, Fair Value [Line Items]
Notional Amount	2,250	2,800
Asset derivatives fair value	66	72
Liability derivatives fair value	38	78
Non-qualifying strategies | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Notional Amount	20,614	19,821
Asset derivatives fair value	184	166
Liability derivatives fair value	420	337
Non-qualifying strategies | Foreign currency options
Derivatives, Fair Value [Line Items]
Notional Amount	9,248	9,553
Asset derivatives fair value	8	0
Liability derivatives fair value	0	0
Non-qualifying strategies | Interest rate swaps
Derivatives, Fair Value [Line Items]
Notional Amount	2,370	7,120
Asset derivatives fair value	21	3
Liability derivatives fair value	0	0
Non-qualifying strategies | Interest rate swaptions
Derivatives, Fair Value [Line Items]
Notional Amount	7	7
Asset derivatives fair value	0	0
Liability derivatives fair value	$ 0	$ 0

DERIVATIVE INSTRUMENTS - Gains

DERIVATIVE INSTRUMENTS - Gains (Losses) Recognized on Fair Value Hedging Relationships (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives		$ (16)	$ 4
Gains (losses) on derivatives excluded from effectiveness testing	[1]	(7)	(15)
Gains (losses) on derivatives included in effectiveness testing	[2]	(9)	19
Gains (losses) recognized for hedged items	[2]	10	(18)
Net realized gains (losses) recognized for fair value hedge		1	1
Fixed maturity securities | Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives		(16)	9
Gains (losses) on derivatives excluded from effectiveness testing	[1]	(7)	(10)
Gains (losses) on derivatives included in effectiveness testing	[2]	(9)	19
Gains (losses) recognized for hedged items	[2]	10	(18)
Net realized gains (losses) recognized for fair value hedge		$ 1	1
Fixed maturity securities | Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives			(4)
Gains (losses) on derivatives excluded from effectiveness testing	[1]		(4)
Gains (losses) on derivatives included in effectiveness testing	[2]		0
Gains (losses) recognized for hedged items	[2]		0
Net realized gains (losses) recognized for fair value hedge			0
Fixed maturity securities | Interest rate swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives			(1)
Gains (losses) on derivatives excluded from effectiveness testing	[1]		(1)
Gains (losses) on derivatives included in effectiveness testing	[2]		0
Gains (losses) recognized for hedged items	[2]		0
Net realized gains (losses) recognized for fair value hedge			$ 0
[1]	Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss).
[2]	Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the three -month periods ended March 31, 2020 and 2019, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial.

DERIVATIVE INSTRUMENTS - Schedu

DERIVATIVE INSTRUMENTS - Schedule of Interest Rate Fair Value Hedges Hedged Items (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		$ 53,291	$ 61,695
Fair value hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		9,115	12,780
Interest rate swaptions | Fair value hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		243	243
Fixed maturity securities | Interest rate swaptions
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying Amount of Hedged Assets/ (Liabilities)	[1]	4,469	4,633
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities)		$ 249	$ 256
[1]	The balance includes hedging adjustment on discontinued hedging relationships of $249 in 2020 and $256 in 2019.

DERIVATIVE INSTRUMENTS - Deriva

DERIVATIVE INSTRUMENTS - Derivatives and Hedging Instruments Gain (Loss) Summary (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	[1]	$ (1)	$ (1)
Unrealized foreign currency translation gains (losses) during period		85	(1)
Derivative gains (losses)		(85)	0
Derivative and non-derivative hedging instruments gain (loss) recognized in other comprehensive income effective portion before tax	[2]	(23)	(3)
Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	[1]	(1)	(1)
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)	[3]	0	0
Gain (loss) recognized in other comprehensive income on derivative (effective portion)	[2]	(4)	(2)
Cash flow hedges | Foreign currency swaps | Variable Interest Entity
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	[1]	(1)	(1)
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		0	0
Gain (loss) recognized in other comprehensive income on derivative (effective portion)	[2]	(4)	(2)
Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	[1]	0	0
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		(6)	(13)
Gain (loss) recognized in other comprehensive income on derivative (effective portion)	[2]	0	(1)
Fair value hedges | Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)	[3]	(6)	(9)
Fair value hedges | Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)	[3]	0	(4)
Fair value hedges | Interest rate swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	[1],[3]	0	0
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)	[3]	0	0
Gain (loss) recognized in other comprehensive income on derivative (effective portion)	[2],[3]	0	(1)
Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		57	0
Unrealized foreign currency translation gains (losses) during period	[2]	(19)	0
Net investment hedge | Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		51	0
Unrealized foreign currency translation gains (losses) during period	[2]	(25)	0
Net investment hedge | Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		6	0
Unrealized foreign currency translation gains (losses) during period	[2]	0	0
Net investment hedge | Non-derivative hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Net realized investment gains (losses) recognized in income on derivative (ineffective portion)		0	0
Unrealized foreign currency translation gains (losses) during period	[2]	6	0
Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		(136)	13
Non-qualifying strategies | Foreign currency swaps | Variable Interest Entity
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		(195)	(16)
Non-qualifying strategies | Foreign currency swaps | Consolidated Entity Excluding Variable Interest Entities (VIE)
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		50	44
Non-qualifying strategies | Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		(36)	(21)
Non-qualifying strategies | Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		(2)	0
Non-qualifying strategies | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net		$ 47	$ 6
[1]	Cash flow hedge items and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses) on derivatives and net investment hedge items are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss).
[2]	Impact of cash flow hedges reported as net investment gains (losses) includes an immaterial amount of gains or losses reclassified from accumulated other comprehensive income (loss) into earnings. It also includes an immaterial amount excluded from effectiveness testing during the three -month periods ended March 31, 2020 and 2019 , respectively.
[3]	Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail)

DERIVATIVE INSTRUMENTS - Offset

DERIVATIVE INSTRUMENTS - Offsetting of Financial Assets and Derivative Assets (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	$ 383	$ 313
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	383	313
Financial instruments, amount not offset	(229)	(190)
Derivative, collateral, obligation to return securities	(7)	(7)
Derivative, collateral, obligation to return cash	(132)	(113)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	15	3
Derivative asset, not subject to master netting arrangement	89	169
Derivative asset, fair value, amount offset against collateral, not subject to master netting agreement	89	169
Derivative asset, fair value, gross asset including not subject to master netting arrangement	472	482
Net amount of derivative assets presented in balance sheet	472	482
Derivative asset, fair value, amount offset against collateral	104	172
Gross amounts of recognized financial instruments	3,424	2,342
Gross amounts offset in balance sheet	0	0
Net amounts of assets presented in balance sheet	3,424	2,342
Carrying value of financial instruments not offset in balance sheet	(229)	(190)
Securities collateral, not offset in balance sheet	(7)	(7)
Cash collateral, not offset in balance sheet	(3,084)	(1,973)
Financial instruments, amount of assets offset against collateral	104	172
Over the Counter - Bilateral
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	362	310
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	362	310
Financial instruments, amount not offset	(229)	(190)
Derivative, collateral, obligation to return securities	(7)	(7)
Derivative, collateral, obligation to return cash	(121)	(113)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	5	0
Derivative asset, not subject to master netting arrangement	89	169
Derivative asset, fair value, amount offset against collateral, not subject to master netting agreement	89	169
Other the Counter - Cleared
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	21	3
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	21	3
Financial instruments, amount not offset	0	0
Derivative, collateral, obligation to return securities	0	0
Derivative, collateral, obligation to return cash	(11)	0
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	10	3
Securities Lending and Similar Arrangements
Offsetting Assets [Line Items]
Gross amounts of recognized financial instruments	2,952	1,860
Gross amounts offset in balance sheet	0	0
Net amounts of assets presented in balance sheet	2,952	1,860
Carrying value of financial instruments not offset in balance sheet	0	0
Securities collateral, not offset in balance sheet	0	0
Cash collateral, not offset in balance sheet	(2,952)	(1,860)
Financial instruments, amount of assets offset against collateral	$ 0	$ 0

DERIVATIVE INSTRUMENTS - Offs_2

DERIVATIVE INSTRUMENTS - Offsetting of Financial Liabilities and Derivative Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	$ 488	$ 460
Gross amount of assets offset in balance sheet	0	0
Derivative liability, fair value, amount not offset against collateral	488	460
Financial instruments, amount not offset	(229)	(190)
Derivative, collateral, right to reclaim securities	(175)	(222)
Derivative, collateral, right to reclaim cash	(2)	(33)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement	82	15
Derivative liability, not subject to master netting arrangement	235	126
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement	235	126
Derivative liability, fair value, gross liability including not subject to master netting arrangement	723	586
Net amount of derivative liabilities presented in balance sheet	723	586
Derivative liability, fair value, amount offset against collateral	317	141
Gross Amounts of Recognized Financial Instruments, Offsetting Liabilities	3,692	2,462
Gross Amounts Offset in Statement of Financial Position, Offsetting Liabilities	0	0
Net Amounts of Financial Instruments Presented in Balance Sheet, Offsetting Liabilities	3,692	2,462
Carrying value of financial instruments, liabilities not offset in balance sheet	(3,181)	(2,050)
Securities Collateral, Liabilities Not Offset in Balance Sheet	(175)	(222)
Cash Collateral, Liabilities Not Offset in Balance Sheet	(2)	(33)
Financial instruments, amount of liabilities offset against collateral	334	157
Over the Counter - Bilateral
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	488	459
Gross amount of assets offset in balance sheet	0	0
Derivative liability, fair value, amount not offset against collateral	488	459
Financial instruments, amount not offset	(229)	(190)
Derivative, collateral, right to reclaim securities	(175)	(222)
Derivative, collateral, right to reclaim cash	(2)	(32)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement	82	15
Derivative liability, not subject to master netting arrangement	235	126
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement	235	126
Exchange Cleared [Member]
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities		1
Gross amount of assets offset in balance sheet		0
Derivative liability, fair value, amount not offset against collateral		1
Financial instruments, amount not offset		0
Derivative, collateral, right to reclaim securities		0
Derivative, collateral, right to reclaim cash		(1)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement		0
Securities Lending and Similar Arrangements
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Financial Instruments, Offsetting Liabilities	2,969	1,876
Gross Amounts Offset in Statement of Financial Position, Offsetting Liabilities	0	0
Net Amounts of Financial Instruments Presented in Balance Sheet, Offsetting Liabilities	2,969	1,876
Carrying value of financial instruments, liabilities not offset in balance sheet	(2,952)	(1,860)
Securities Collateral, Liabilities Not Offset in Balance Sheet	0	0
Cash Collateral, Liabilities Not Offset in Balance Sheet	0	0
Financial instruments, amount of liabilities offset against collateral	$ 17	$ 16

FAIR VALUE MEASUREMENTS - Fair

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Assets:
Available for sale, fixed maturity securities	$ 96,288	$ 91,262
Equity securities	660	802
Other investments	892	628
Cash and cash equivalents	4,148	4,896
Asset derivatives	472	482
Total assets	102,460	98,070
Liabilities:
Liability derivatives	723	586
Total liabilities	723	586
Foreign currency swaps
Assets:
Asset derivatives	155	241
Liabilities:
Liability derivatives	273	204
Foreign currency forwards
Assets:
Asset derivatives	269	238
Liabilities:
Liability derivatives	427	377
Foreign currency options
Assets:
Asset derivatives	27
Liabilities:
Liability derivatives	23	5
Interest rate swaps
Assets:
Asset derivatives	21	3
Government and agencies
Assets:
Available for sale, fixed maturity securities	36,978	36,400
Municipalities
Assets:
Available for sale, fixed maturity securities	2,440	1,847
Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	497	410
Public utilities
Assets:
Available for sale, fixed maturity securities	9,192	6,780
Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	1,609	1,042
Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	10,378	10,287
Other corporate
Assets:
Available for sale, fixed maturity securities	35,194	34,496
Level 1
Assets:
Available for sale, fixed maturity securities	35,469	34,878
Equity securities	509	642
Other investments	892	628
Cash and cash equivalents	4,148	4,896
Asset derivatives	0	0
Total assets	41,018	41,044
Liabilities:
Total liabilities	0	0
Level 1 | Foreign currency swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Foreign currency options
Assets:
Asset derivatives	0
Liabilities:
Liability derivatives	0	0
Level 1 | Interest rate swaps
Assets:
Asset derivatives	0	0
Level 1 | Government and agencies
Assets:
Available for sale, fixed maturity securities	35,469	34,878
Level 1 | Municipalities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 | Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 | Public utilities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 | Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 | Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 | Other corporate
Assets:
Available for sale, fixed maturity securities	0	0
Level 2
Assets:
Available for sale, fixed maturity securities	60,065	55,697
Equity securities	69	80
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	383	313
Total assets	60,517	56,090
Liabilities:
Total liabilities	488	460
Level 2 | Foreign currency swaps
Assets:
Asset derivatives	66	72
Liabilities:
Liability derivatives	38	78
Level 2 | Foreign currency forwards
Assets:
Asset derivatives	269	238
Liabilities:
Liability derivatives	427	377
Level 2 | Foreign currency options
Assets:
Asset derivatives	27
Liabilities:
Liability derivatives	23	5
Level 2 | Interest rate swaps
Assets:
Asset derivatives	21	3
Level 2 | Government and agencies
Assets:
Available for sale, fixed maturity securities	1,509	1,522
Level 2 | Municipalities
Assets:
Available for sale, fixed maturity securities	2,440	1,847
Level 2 | Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	309	232
Level 2 | Public utilities
Assets:
Available for sale, fixed maturity securities	8,894	6,556
Level 2 | Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	1,609	1,042
Level 2 | Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	10,355	10,264
Level 2 | Other corporate
Assets:
Available for sale, fixed maturity securities	34,949	34,234
Level 3
Assets:
Available for sale, fixed maturity securities	754	687
Equity securities	82	80
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	89	169
Total assets	925	936
Liabilities:
Total liabilities	235	126
Level 3 | Foreign currency swaps
Assets:
Asset derivatives	89	169
Liabilities:
Liability derivatives	235	126
Level 3 | Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 3 | Foreign currency options
Assets:
Asset derivatives	0
Liabilities:
Liability derivatives	0	0
Level 3 | Interest rate swaps
Assets:
Asset derivatives	0	0
Level 3 | Government and agencies
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 | Municipalities
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 | Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	188	178
Level 3 | Public utilities
Assets:
Available for sale, fixed maturity securities	298	224
Level 3 | Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 | Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	23	23
Level 3 | Other corporate
Assets:
Available for sale, fixed maturity securities	$ 245	$ 262

FAIR VALUE MEASUREMENTS - Fai_2

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost (Details) - USD ($) $ in Millions	Mar. 31, 2020		Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	$ 1,843		$ 1,477
Assets:
Securities held to maturity, fixed maturities, amortized cost	23,287		30,085
Held to maturity, fixed maturity securities, fair value	29,347		37,594
Commercial mortgage and other loans	10,750		9,569
Commercial mortgage and other loans, fair value	10,390		9,648
Other investments carried at amortized cost	29	[1]	30	[2]
Other investments carried at amortized cost, fair value	29	[1]	30	[2]
Total financial instruments assets not carried at fair value	34,057		39,684
Assets fair value disclosure financial instruments carried at cost	39,766		47,272
Liabilities:
Other policyholders’ funds	7,422		7,317
Other policyholders' funds fair value disclosure	7,338		7,234
Notes payable	6,597		6,408
Notes payable, fair value disclosure	6,881		6,935
Total financial instrument liabilities not carried at fair value	14,019		13,725
Liabilities fair value disclosure financial instruments carried at cost	14,219		14,169
Government and agencies
Assets:
Securities held to maturity, fixed maturities, amortized cost	22,384		22,241
Held to maturity, fixed maturity securities, fair value	28,194		28,291
Municipalities
Assets:
Securities held to maturity, fixed maturities, amortized cost	362		821
Held to maturity, fixed maturity securities, fair value	484		1,083
Mortgage- and asset-backed securities
Assets:
Securities held to maturity, fixed maturities, amortized cost			16
Held to maturity, fixed maturity securities, fair value			17
Public utilities
Assets:
Securities held to maturity, fixed maturities, amortized cost	45		2,535
Held to maturity, fixed maturity securities, fair value	59		2,954
Sovereign and supranational
Assets:
Securities held to maturity, fixed maturities, amortized cost	464		1,123
Held to maturity, fixed maturity securities, fair value	578		1,320
Banks/financial institutions
Assets:
Securities held to maturity, fixed maturities, amortized cost			916
Held to maturity, fixed maturity securities, fair value			1,018
Other corporate
Assets:
Securities held to maturity, fixed maturities, amortized cost	23		2,433
Held to maturity, fixed maturity securities, fair value	32		2,911
Policy loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	253		250
Equity method investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	669		569
Level 1
Assets:
Held to maturity, fixed maturity securities, fair value	27,842		27,937
Commercial mortgage and other loans, fair value	0		0
Other investments carried at amortized cost, fair value	0	[1]	0	[2]
Assets fair value disclosure financial instruments carried at cost	27,842		27,937
Liabilities:
Other policyholders' funds fair value disclosure	0		0
Notes payable, fair value disclosure	0		0
Liabilities fair value disclosure financial instruments carried at cost	0		0
Level 1 | Government and agencies
Assets:
Held to maturity, fixed maturity securities, fair value	27,842		27,937
Level 1 | Municipalities
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 1 | Mortgage- and asset-backed securities
Assets:
Held to maturity, fixed maturity securities, fair value			0
Level 1 | Public utilities
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 1 | Sovereign and supranational
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 1 | Banks/financial institutions
Assets:
Held to maturity, fixed maturity securities, fair value			0
Level 1 | Other corporate
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 2
Assets:
Held to maturity, fixed maturity securities, fair value	1,505		9,647
Commercial mortgage and other loans, fair value	0		0
Other investments carried at amortized cost, fair value	29	[1]	30	[2]
Assets fair value disclosure financial instruments carried at cost	1,534		9,677
Liabilities:
Other policyholders' funds fair value disclosure	0		0
Notes payable, fair value disclosure	6,607		6,663
Liabilities fair value disclosure financial instruments carried at cost	6,607		6,663
Level 2 | Government and agencies
Assets:
Held to maturity, fixed maturity securities, fair value	352		354
Level 2 | Municipalities
Assets:
Held to maturity, fixed maturity securities, fair value	484		1,083
Level 2 | Mortgage- and asset-backed securities
Assets:
Held to maturity, fixed maturity securities, fair value			7
Level 2 | Public utilities
Assets:
Held to maturity, fixed maturity securities, fair value	59		2,954
Level 2 | Sovereign and supranational
Assets:
Held to maturity, fixed maturity securities, fair value	578		1,320
Level 2 | Banks/financial institutions
Assets:
Held to maturity, fixed maturity securities, fair value			1,018
Level 2 | Other corporate
Assets:
Held to maturity, fixed maturity securities, fair value	32		2,911
Level 3
Assets:
Held to maturity, fixed maturity securities, fair value	0		10
Commercial mortgage and other loans, fair value	10,390		9,648
Other investments carried at amortized cost, fair value	0	[1]	0	[2]
Assets fair value disclosure financial instruments carried at cost	10,390		9,658
Liabilities:
Other policyholders' funds fair value disclosure	7,338		7,234
Notes payable, fair value disclosure	274		272
Liabilities fair value disclosure financial instruments carried at cost	7,612		7,506
Level 3 | Government and agencies
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 3 | Municipalities
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 3 | Mortgage- and asset-backed securities
Assets:
Held to maturity, fixed maturity securities, fair value			10
Level 3 | Public utilities
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 3 | Sovereign and supranational
Assets:
Held to maturity, fixed maturity securities, fair value	0		0
Level 3 | Banks/financial institutions
Assets:
Held to maturity, fixed maturity securities, fair value			0
Level 3 | Other corporate
Assets:
Held to maturity, fixed maturity securities, fair value	$ 0		$ 0
[1]	Excludes policy loans of $253 and equity method investments of $669 , at carrying value
[2]	Excludes policy loans of $250 and equity method investments of $569 , at carrying value

FAIR VALUE MEASUREMENTS - Fai_3

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets by Pricing Source, Securities Carried at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	$ 96,288	$ 91,262
Equity securities	660	802
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	35,469	34,878
Equity securities	509	642
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	60,065	55,697
Equity securities	69	80
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	754	687
Equity securities	82	80
Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	578	722
Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	509	642
Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	69	80
Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Net asset value valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	82	80
Net asset value valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Net asset value valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Net asset value valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	82	80
Government and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	36,978	36,400
Government and agencies | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	35,469	34,878
Government and agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,509	1,522
Government and agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Government and agencies | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	36,978	36,400
Government and agencies | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	35,469	34,878
Government and agencies | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,509	1,522
Government and agencies | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Municipalities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	2,440	1,847
Municipalities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Municipalities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	2,440	1,847
Municipalities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Municipalities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	2,440	1,847
Municipalities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Municipalities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	2,440	1,847
Municipalities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	497	410
Mortgage- and asset-backed securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	309	232
Mortgage- and asset-backed securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	188	178
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	309	232
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	309	232
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	188	178
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	188	178
Public utilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	9,192	6,780
Public utilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Public utilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	8,894	6,556
Public utilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	298	224
Public utilities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	8,894	6,556
Public utilities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Public utilities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	8,894	6,556
Public utilities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Public utilities | Discounted cash flow technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	298	224
Public utilities | Discounted cash flow technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Public utilities | Discounted cash flow technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Public utilities | Discounted cash flow technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	298	224
Sovereign and supranational
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,609	1,042
Sovereign and supranational | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Sovereign and supranational | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,609	1,042
Sovereign and supranational | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Sovereign and supranational | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,609	1,042
Sovereign and supranational | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Sovereign and supranational | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	1,609	1,042
Sovereign and supranational | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	10,378	10,287
Banks/financial institutions | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	10,355	10,264
Banks/financial institutions | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	23	23
Banks/financial institutions | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	10,355	10,264
Banks/financial institutions | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	10,355	10,264
Banks/financial institutions | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	23	23
Banks/financial institutions | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Banks/financial institutions | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	23	23
Other corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	35,194	34,496
Other corporate | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Other corporate | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	34,949	34,234
Other corporate | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	245	262
Other corporate | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	34,949	34,234
Other corporate | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Other corporate | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	34,949	34,234
Other corporate | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Other corporate | Discounted cash flow technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	245	262
Other corporate | Discounted cash flow technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Other corporate | Discounted cash flow technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	0	0
Other corporate | Discounted cash flow technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale, fixed maturity securities	$ 245	$ 262

FAIR VALUE MEASUREMENTS - Fai_4

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets by Pricing Source, Securities Carried at Amortized Cost (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	$ 29,347	$ 37,594
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	27,842	27,937
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	1,505	9,647
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	10
Government and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	28,194	28,291
Government and agencies | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	27,842	27,937
Government and agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	352	354
Government and agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Government and agencies | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	28,194	28,291
Government and agencies | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	27,842	27,937
Government and agencies | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	352	354
Government and agencies | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Municipalities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	484	1,083
Municipalities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Municipalities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	484	1,083
Municipalities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Municipalities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	484	1,083
Municipalities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Municipalities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	484	1,083
Municipalities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Mortgage- and asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		17
Mortgage- and asset-backed securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Mortgage- and asset-backed securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		7
Mortgage- and asset-backed securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		10
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		7
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		7
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Mortgage- and asset-backed securities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		10
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		10
Public utilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	59	2,954
Public utilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Public utilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	59	2,954
Public utilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Public utilities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	59	2,954
Public utilities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Public utilities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	59	2,954
Public utilities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Sovereign and supranational
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	578	1,320
Sovereign and supranational | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Sovereign and supranational | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	578	1,320
Sovereign and supranational | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Sovereign and supranational | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	578	1,320
Sovereign and supranational | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Sovereign and supranational | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	578	1,320
Sovereign and supranational | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Banks/financial institutions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		1,018
Banks/financial institutions | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Banks/financial institutions | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		1,018
Banks/financial institutions | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Banks/financial institutions | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		1,018
Banks/financial institutions | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Banks/financial institutions | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		1,018
Banks/financial institutions | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value		0
Other corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	32	2,911
Other corporate | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Other corporate | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	32	2,911
Other corporate | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Other corporate | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	32	2,911
Other corporate | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	0	0
Other corporate | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	32	2,911
Other corporate | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity, fixed maturity securities, fair value	$ 0	$ 0

FAIR VALUE MEASUREMENTS - Chang

FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020		Mar. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		$ 810		$ 648
Net investment gains (losses) included in earnings		(185)		(8)
Unrealized gains (losses) included in other comprehensive income (loss)		(28)		1
Purchases		85		63
Issuances		0		0
Sales		0		(2)
Settlements		(1)		0
Transfers into Level 3		9		25
Transfers out of Level 3		0		(41)
Balance, end of period		690		686
Change in unrealized gains (losses) still held		(185)		(8)
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	[1]	43		80
Net investment gains (losses) included in earnings	[1]	(185)		(8)
Unrealized gains or losses included in other comprehensive income (loss)	[1]	(4)		(2)
Purchases	[1]	0		0
Issuances	[1]	0		0
Sales	[1]	0		0
Settlements	[1]	0		0
Transfers into Level 3	[1]	0		0
Transfers out of Level 3	[1]	0		0
Balance, end of period	[1]	(146)		70
Changes in unrealized gain (losses) still held	[1]	(185)		(8)
Credit default swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	[1]	0		0
Net investment gains (losses) included in earnings	[1]	0		0
Unrealized gains or losses included in other comprehensive income (loss)	[1]	0		0
Purchases	[1]	0		0
Issuances	[1]	0		0
Sales	[1]	0		0
Settlements	[1]	0		0
Transfers into Level 3	[1]	0		0
Transfers out of Level 3	[1]	0		0
Balance, end of period	[1]	0		0
Changes in unrealized gain (losses) still held	[1]	0		0
Fixed maturity securities | Mortgage- and asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		178		177
Net investment gains (losses) included in earnings		0		0
Unrealized gains (losses) included in other comprehensive income (loss)		1		1
Purchases		0		0
Issuances		0		0
Sales		0		0
Settlements		0		0
Transfers into Level 3		9	[2]	0
Transfers out of Level 3		0		0
Balance, end of period		188		178
Change in unrealized gains (losses) still held		0		0
Fixed maturity securities | Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		224		109
Net investment gains (losses) included in earnings		0		0
Unrealized gains (losses) included in other comprehensive income (loss)		(8)		1
Purchases		83		0
Issuances		0		0
Sales		0		0
Settlements		(1)		0
Transfers into Level 3		0		0
Transfers out of Level 3		0		(25)	[3]
Balance, end of period		298		85
Change in unrealized gains (losses) still held		0		0
Fixed maturity securities | Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		23		23
Net investment gains (losses) included in earnings		0		0
Unrealized gains (losses) included in other comprehensive income (loss)		0		0
Purchases		0		0
Issuances		0		0
Sales		0		0
Settlements		0		0
Transfers into Level 3		0		0
Transfers out of Level 3		0		0
Balance, end of period		23		23
Change in unrealized gains (losses) still held		0		0
Fixed maturity securities | Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		262		213
Net investment gains (losses) included in earnings		0		0
Unrealized gains (losses) included in other comprehensive income (loss)		(17)		1
Purchases		0		63
Issuances		0		0
Sales		0		(2)
Settlements		0		0
Transfers into Level 3		0		25	[3]
Transfers out of Level 3		0		(16)	[4]
Balance, end of period		245		284
Change in unrealized gains (losses) still held		0		0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		80		46
Net investment gains (losses) included in earnings		0		0
Unrealized gains (losses) included in other comprehensive income (loss)		0		0
Purchases		2		0
Issuances		0		0
Sales		0		0
Settlements		0		0
Transfers into Level 3		0		0
Transfers out of Level 3		0		0
Balance, end of period		82		46
Change in unrealized gains (losses) still held		$ 0		$ 0
[1]	Derivative assets and liabilities are presented net
[2]	Transfer due to reclassification of level 3 securities from HTM to AFS
[3]	Transfer due to sector classification change
[4]	Transfer due to availability of observable market inputs

FAIR VALUE MEASUREMENTS - Fai_5

FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Millions		Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 96,288	$ 91,262
Equity securities		660	802
Asset derivatives		472	482
Liability derivatives		723	586
Assets, fair value		102,460	98,070
Liabilities, fair value		723	586
Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		754	687
Equity securities		82	80
Asset derivatives		89	169
Assets, fair value		925	936
Liabilities, fair value		235	126
Net asset value valuation technique
Fair Value Measurement Inputs and Valuation Techniques
Equity securities		82	80
Net asset value valuation technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Equity securities		82	80
Foreign currency swaps
Fair Value Measurement Inputs and Valuation Techniques
Asset derivatives		155	241
Liability derivatives		273	204
Foreign currency swaps | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Asset derivatives		89	169
Liability derivatives		235	126
Foreign currency swaps | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Discounted cash flow technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Asset derivatives		15	106
Liability derivatives		224	118
Foreign currency swaps | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Discounted cash flow technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Asset derivatives		74	63
Liability derivatives		$ 11	$ 8
Foreign currency swaps | Credit Spread | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Lower Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input		0.0031	0.0010
Derivative liability, measurement input		0.0031	0.0013
Foreign currency swaps | Credit Spread | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Upper Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input		0.0173	0.0100
Derivative liability, measurement input		0.0173	0.0159
Dollar-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 36,893	$ 38,281
Equity securities		$ 132	$ 144
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Lower Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[1]	0.0072	0.0189
Derivative liability, measurement input	[1]	0.0072	0.0189
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Upper Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[1]	0.0088	0.0209
Derivative liability, measurement input	[1]	0.0088	0.0209
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Lower Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[1]	0.0072	0.0189
Derivative liability, measurement input	[1]	0.0072	0.0189
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Upper Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[1]	0.0088	0.0209
Derivative liability, measurement input	[1]	0.0088	0.0209
Yen-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 59,395	$ 52,981
Equity securities		$ 528	$ 658
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Lower Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[2]	0.0002	0.0012
Derivative liability, measurement input	[2]	0.0002	0.0012
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY) and CDS Spreads | Upper Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[2]	0.0020	0.0043
Derivative liability, measurement input	[2]	0.0020	0.0043
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Lower Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[2]	0.0002	0.0012
Derivative liability, measurement input	[2]	0.0002	0.0012
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Upper Limit | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Derivative asset, measurement input	[2]	0.0020	0.0043
Derivative liability, measurement input	[2]	0.0020	0.0043
Mortgage- and asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 497	$ 410
Mortgage- and asset-backed securities | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		188	178
Mortgage- and asset-backed securities | Consensus pricing valuation technique
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		188	178
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		188	178
Mortgage- and asset-backed securities | Dollar-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		160	156
Mortgage- and asset-backed securities | Yen-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		337	254
Banks/financial institutions
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		10,378	10,287
Banks/financial institutions | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		23	23
Banks/financial institutions | Consensus pricing valuation technique
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		23	23
Banks/financial institutions | Consensus pricing valuation technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		23	23
Banks/financial institutions | Dollar-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		3,372	3,521
Banks/financial institutions | Yen-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		7,006	6,766
Public utilities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		9,192	6,780
Public utilities | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		298	224
Public utilities | Discounted cash flow technique
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		298	224
Public utilities | Discounted cash flow technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		298	224
Public utilities | Dollar-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		4,443	4,519
Public utilities | Yen-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		4,749	2,261
Other corporate
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		35,194	34,496
Other corporate | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		245	262
Other corporate | Discounted cash flow technique
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		245	262
Other corporate | Discounted cash flow technique | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		245	262
Other corporate | Dollar-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		27,013	28,253
Other corporate | Yen-denominated
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 8,181	$ 6,243
[1]	Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps
[2]	Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps

POLICY LIABILITIES - Changes in

POLICY LIABILITIES - Changes in Liability for Unpaid Policy Claims (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Liability for Unpaid Claims and Claims Expenses
Net balance, beginning of period	$ 4,659
Less claims paid during the period on claims incurred during:
Net balance, end of period	4,693
Total liability for unpaid policy claims	4,693	$ 4,625
Health insurance
Liability for Unpaid Claims and Claims Expenses
Unpaid supplemental health claims, beginning of period	3,968	3,952
Less reinsurance recoverables	31	29
Net balance, beginning of period	3,937	3,923
Add claims incurred during the period related to:
Current year	1,837	1,825
Prior years	(136)	(167)
Total incurred	1,701	1,658
Less claims paid during the period on claims incurred during:
Current year	556	506
Prior years	1,144	1,137
Total paid	1,700	1,643
Effect of foreign exchange rate changes on unpaid claims	12	0
Net balance, end of period	3,950	3,938
Add reinsurance recoverables	33	29
Total liability for unpaid policy claims	3,983	3,967
Life insurance
Less claims paid during the period on claims incurred during:
Total liability for unpaid policy claims	$ 710	$ 658

POLICY LIABILITIES - Additional

POLICY LIABILITIES - Additional Information (Details) - Health insurance - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years claims and claims adjustment expense	$ (136)	$ (167)
Aflac Japan
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years claims and claims adjustment expense	$ 91
Percentage of total prior year claims and claims adjustment expense	67.00%
Liability for unpaid claims and claims adjustment expense, foreign currency translation gain (loss), prior year claims adjustment expense	$ 1
Prior year claims and claims adjustment expense excluding effect of foreign currency	$ 90
Percentage of total prior year claims and claims adjustment expense excluding effect of foreign currency	66.00%

REINSURANCE - Additional Infor

REINSURANCE - Additional Information (Details) $ in Millions, ¥ in Billions	3 Months Ended
	Mar. 31, 2020JPY (¥)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Effects of Reinsurance [Line Items]
Percent change in spot yen/dollar exchange rate		0.70%
Percent change in ceded reserves		2.30%
Aflac Japan
Effects of Reinsurance [Line Items]
Committed reinsurance facility | ¥	¥ 110
Aflac Japan | Closed Block
Effects of Reinsurance [Line Items]
Reinsurance deferred profit liability		$ 1,000	$ 1,000
Reinsurance recoverable		$ 976	$ 970

REINSURANCE - Effect of Reinsu

REINSURANCE - Effect of Reinsurance on Premiums and Benefits and Claims (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Effects of Reinsurance [Line Items]
Direct premium income	$ 4,772	$ 4,776
Net premium income	4,681	4,691
Direct benefits and claims	3,028	3,041
Benefits and claims, net	2,939	2,967
All other
Effects of Reinsurance [Line Items]
Ceded premiums	(24)	(15)
Assumed premiums earned	0	1
Ceded benefits and claims	(25)	(11)
Assumed benefits and claims from other companies	0	0
Aflac Japan
Effects of Reinsurance [Line Items]
Net premium income	3,150	3,180
Aflac Japan | Closed Block
Effects of Reinsurance [Line Items]
Ceded premiums	(116)	(121)
Assumed premiums earned	49	50
Ceded benefits and claims	(105)	(111)
Assumed benefits and claims from other companies	41	48
Intercompany eliminations
Effects of Reinsurance [Line Items]
Ceded benefits and claims	10	10
Assumed benefits and claims from other companies	$ (10)	$ (10)

NOTES PAYABLE AND LEASE OBLIG_3

NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Details) $ in Millions, ¥ in Billions	1 Months Ended
	Jan. 31, 2020USD ($)	Mar. 31, 2020JPY (¥)series	Mar. 31, 2020USD ($)series	Dec. 31, 2019JPY (¥)
Debt Instrument [Line Items]
Number of Series of Senior Notes Issued Through a U.S. Public Debt Offering | series		4	4
Lines of credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount | $			$ 0
.936% subordinate bond due April 2049
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 30		¥ 30
Debt instrument, interest rate		0.963%	0.963%	0.963%
Notes payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount | $			$ 0
Senior notes
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 57
.300% senior notes due September 2025
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 12.4
Debt instrument, interest rate		0.30%	0.30%
.550% senior notes due March 2030
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 13.3
Debt instrument, interest rate		0.55%	0.55%
.750% senior notes due March 2032
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 20.7
Debt instrument, interest rate		0.75%	0.75%
.830% senior notes due March 2035
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 10.6
Debt instrument, interest rate		0.83%	0.83%
4.00% senior notes paid January 2020
Debt Instrument [Line Items]
Debt instrument, interest rate	4.00%	4.00%	4.00%	4.00%
Repayments of debt | $	$ 350

NOTES PAYABLE AND LEASE OBLIG_4

NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Notes Payable (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Notes payable and lease obligations	$ 6,758	$ 6,569
Finance lease obligations	12	12
Operating lease obligations	149	149
4.00% senior notes paid January 2020
Debt Instrument [Line Items]
Notes payable and lease obligations	0	348
3.625% senior notes due June 2023
Debt Instrument [Line Items]
Notes payable and lease obligations	698	698
3.625% senior notes due November 2024
Debt Instrument [Line Items]
Notes payable and lease obligations	747	747
3.25% senior notes due March 2025
Debt Instrument [Line Items]
Notes payable and lease obligations	448	448
2.875% senior notes due October 2026
Debt Instrument [Line Items]
Notes payable and lease obligations	298	298
6.90% senior notes due December 2039
Debt Instrument [Line Items]
Notes payable and lease obligations	220	220
6.45% senior notes due August 2040
Debt Instrument [Line Items]
Notes payable and lease obligations	254	254
4.00% senior notes due October 2046
Debt Instrument [Line Items]
Notes payable and lease obligations	393	394
4.750% senior notes due January 2049
Debt Instrument [Line Items]
Notes payable and lease obligations	541	541
.300% senior notes due September 2025
Debt Instrument [Line Items]
Notes payable and lease obligations	113	0
.932% senior notes due January 2027
Debt Instrument [Line Items]
Notes payable and lease obligations	549	545
.500% senior noted due December 2029
Debt Instrument [Line Items]
Notes payable and lease obligations	115	114
.550% senior notes due March 2030
Debt Instrument [Line Items]
Notes payable and lease obligations	121	0
1.159% senior notes due October 2030
Debt Instrument [Line Items]
Notes payable and lease obligations	268	266
.843% senior notes due December 2031
Debt Instrument [Line Items]
Notes payable and lease obligations	85	84
.750% senior notes due March 2032
Debt Instrument [Line Items]
Notes payable and lease obligations	189	0
1.488% senior notes due October 2033
Debt Instrument [Line Items]
Notes payable and lease obligations	139	138
.934% senior notes due December 2034
Debt Instrument [Line Items]
Notes payable and lease obligations	89	88
.830% senior notes due March 2035
Debt Instrument [Line Items]
Notes payable and lease obligations	97	0
1.750% senior notes due October 2038
Debt Instrument [Line Items]
Notes payable and lease obligations	81	81
1.122% senior notes due December 2039
Debt Instrument [Line Items]
Notes payable and lease obligations	57	57
2.108% subordinated notes due October 2047
Debt Instrument [Line Items]
Notes payable and lease obligations	547	543
.936% subordinate bond due April 2049
Debt Instrument [Line Items]
Notes payable and lease obligations	274	272
Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Notes payable and lease obligations	46	45
Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Notes payable and lease obligations	$ 228	$ 227

NOTES PAYABLE AND LEASE OBLIG_5

NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Notes Payable (Parenthetical) (Details) - JPY (¥) ¥ in Billions	Mar. 31, 2020	Jan. 31, 2020	Dec. 31, 2019
4.00% senior notes paid January 2020
Debt Instrument [Line Items]
Debt instrument, interest rate	4.00%	4.00%	4.00%
3.625% senior notes due June 2023
Debt Instrument [Line Items]
Debt instrument, interest rate	3.625%		3.625%
3.625% senior notes due November 2024
Debt Instrument [Line Items]
Debt instrument, interest rate	3.625%		3.625%
3.25% senior notes due March 2025
Debt Instrument [Line Items]
Debt instrument, interest rate	3.25%		3.25%
2.875% senior notes due October 2026
Debt Instrument [Line Items]
Debt instrument, interest rate	2.875%		2.875%
6.90% senior notes due December 2039
Debt Instrument [Line Items]
Debt instrument, interest rate	6.90%		6.90%
6.45% senior notes due August 2040
Debt Instrument [Line Items]
Debt instrument, interest rate	6.45%		6.45%
4.00% senior notes due October 2046
Debt Instrument [Line Items]
Debt instrument, interest rate	4.00%		4.00%
4.750% senior notes due January 2049
Debt Instrument [Line Items]
Debt instrument, interest rate	4.75%		4.75%
.300% senior notes due September 2025
Debt Instrument [Line Items]
Debt instrument, interest rate	0.30%
Debt instrument, principal amount	¥ 12.4
.932% senior notes due January 2027
Debt Instrument [Line Items]
Debt instrument, interest rate	0.932%		0.932%
Debt instrument, principal amount	¥ 60		¥ 60
.500% senior noted due December 2029
Debt Instrument [Line Items]
Debt instrument, interest rate	0.50%		0.50%
Debt instrument, principal amount	¥ 12.6		¥ 12.6
.550% senior notes due March 2030
Debt Instrument [Line Items]
Debt instrument, interest rate	0.55%
Debt instrument, principal amount	¥ 13.3
1.159% senior notes due October 2030
Debt Instrument [Line Items]
Debt instrument, interest rate	1.159%		1.159%
Debt instrument, principal amount	¥ 29.3		¥ 29.3
.843% senior notes due December 2031
Debt Instrument [Line Items]
Debt instrument, interest rate	0.843%		0.843%
Debt instrument, principal amount	¥ 9.3		¥ 9.3
.750% senior notes due March 2032
Debt Instrument [Line Items]
Debt instrument, interest rate	0.75%
Debt instrument, principal amount	¥ 20.7
1.488% senior notes due October 2033
Debt Instrument [Line Items]
Debt instrument, interest rate	1.488%		1.488%
Debt instrument, principal amount	¥ 15.2		¥ 15.2
.934% senior notes due December 2034
Debt Instrument [Line Items]
Debt instrument, interest rate	0.934%		0.934%
Debt instrument, principal amount	¥ 9.8		¥ 9.8
.830% senior notes due March 2035
Debt Instrument [Line Items]
Debt instrument, interest rate	0.83%
Debt instrument, principal amount	¥ 10.6
1.750% senior notes due October 2038
Debt Instrument [Line Items]
Debt instrument, interest rate	1.75%		1.75%
Debt instrument, principal amount	¥ 8.9		¥ 8.9
1.122% senior notes due December 2039
Debt Instrument [Line Items]
Debt instrument, interest rate	1.122%		1.122%
Debt instrument, principal amount	¥ 6.3		¥ 6.3
2.108% subordinated notes due October 2047
Debt Instrument [Line Items]
Debt instrument, interest rate	2.108%		2.108%
Debt instrument, principal amount	¥ 60		¥ 60
.936% subordinate bond due April 2049
Debt Instrument [Line Items]
Debt instrument, interest rate	0.963%		0.963%
Debt instrument, principal amount	¥ 30		¥ 30
Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, interest rate	0.42%		0.42%
Debt instrument, principal amount	¥ 5		¥ 5
Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Debt instrument, interest rate	0.57%		0.57%
Debt instrument, principal amount	¥ 25		¥ 25

NOTES PAYABLE AND LEASE OBLIG_6

NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Lines of Credit (Details) - 3 months ended Mar. 31, 2020 ¥ in Millions, $ in Millions	JPY (¥)	USD ($)
$100 million line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	The rate quoted by the bank and agreed upon at the time of borrowing
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity		$ 100
Line of credit facility, amount outstanding		0
100.0 billion yen line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out period
Line of credit facility term	5 years
Line of credit facility, maximum borrowing capacity | ¥	¥ 100,000
Line of credit facility, amount outstanding | ¥	¥ 0
$1 billion line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	A rate per annum equal to, at the Company's option, either, (a) LIBOR adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin
Line of credit facility term	5 years
Line of credit facility, maximum borrowing capacity		1,000
Line of credit facility, amount outstanding		0
$50 million line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	A rate per annum equal to, at the Parent Company's option, either (a) a eurocurrency rate determined by reference to the agent's LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the greater of (i) the prime rate as determined by the agent, and (ii) the sum of 0.50% and the federal funds rate for such day
Line of credit facility, maximum borrowing capacity		50
Line of credit facility, amount outstanding		0
$250 million line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	USD three-month LIBOR plus 75 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity		250
Line of credit facility, amount outstanding		82
Debt instrument, term	3 months
50.0 billion yen line of credit expiring April 2020
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	Three-month TIBOR plus 70 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity | ¥	¥ 50,000
Line of credit facility, amount outstanding | ¥	¥ 0
Debt instrument, term	3 months
50.0 billion yen line of credit expiring November 2020
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	Three-month TIBOR plus 70 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity | ¥	¥ 50,000
Line of credit facility, amount outstanding | ¥	¥ 0
Debt instrument, term	3 months
$25 million line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	USD three-month LIBOR plus 75 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity		25
Line of credit facility, amount outstanding		0
Debt instrument, term	3 months
$15 million line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	USD three-month LIBOR plus 75 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity		15
Line of credit facility, amount outstanding		0
Debt instrument, term	3 months
$300 thousand line of credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	USD three-month LIBOR plus 75 basis points per annum
Line of credit facility term	364 days
Line of credit facility, maximum borrowing capacity		0.3
Line of credit facility, amount outstanding		$ 0
Debt instrument, term	3 months
Lower Limit | 100.0 billion yen line of credit
Line of Credit Facility [Line Items]
Line of credit facility, commitment fee percentage	0.30%
Lower Limit | $1 billion line of credit
Line of Credit Facility [Line Items]
Line of credit facility, commitment fee percentage	0.085%
Upper Limit | $100 million line of credit
Line of Credit Facility [Line Items]
Debt instrument, term	3 months
Upper Limit | 100.0 billion yen line of credit
Line of Credit Facility [Line Items]
Line of credit facility, commitment fee percentage	0.50%
Upper Limit | $1 billion line of credit
Line of Credit Facility [Line Items]
Line of credit facility, commitment fee percentage	0.225%
Upper Limit | $50 million line of credit
Line of Credit Facility [Line Items]
Debt instrument, term	3 months

INCOME TAXES - Additional Infor

INCOME TAXES - Additional Information (Details)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Blended statutory income tax rate	21.40%	25.30%
Japan tax rate	28.00%

SHAREHOLDERS' EQUITY - Reconcil

SHAREHOLDERS' EQUITY - Reconciliation of Number of Shares of Common Stock (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Common Stock Issued [Roll Forward]
Balance, beginning of period	1,349,309	1,347,540
Exercise of stock options and issuance of restricted shares	1,341	1,060
Balance, end of period	1,350,650	1,348,600
Treasury Stock [Roll Forward]
Balance, beginning of period	622,516	592,254
Balance, end of period	632,268	602,113
Shares outstanding, end of period	718,382	746,487
Treasury Stock
Treasury Stock [Roll Forward]
Stock acquired under share repurchase program, shares	9,984	10,237
Other purchases	508	561
Shares issued to AFL Stock Plan	(468)	(430)
Exercise of stock options	(45)	(231)
Other dispositions	(227)	(278)

SHAREHOLDERS' EQUITY - Anti-Dil

SHAREHOLDERS' EQUITY - Anti-Dilutive Share-Based Awards Excluded from Calculation of Diluted Earnings Per Share (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stockholders' Equity Note [Abstract]
Anti-dilutive share-based awards	744	22

SHAREHOLDERS' EQUITY - Addition

SHAREHOLDERS' EQUITY - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stockholders Equity Note [Line Items]
Common stock, share repurchase, dollar amount	$ 449	$ 490
Remaining common stock available for purchase under share repurchase authorizations	27.1
Share Repurchase Program
Stockholders Equity Note [Line Items]
Stock acquired under share repurchase program, shares	10	10.2
Common stock, share repurchase, dollar amount	$ 449	$ 490

SHAREHOLDERS' EQUITY - Changes

SHAREHOLDERS' EQUITY - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	$ 6,615	$ 2,151
Adjusted balance, beginning of period	7,463
Other comprehensive income (loss) before reclassifications net of tax	(3,287)	2,340
Amounts reclassified from accumulated other comprehensive income net of tax	12	(10)
Other comprehensive income (loss), net of tax	(3,275)	2,330
Balance, end of period	4,188	4,481
Accounting Standards Update 2019-04
Accumulated Other Comprehensive Income [Roll Forward]
Amounts reclassified from accumulated other comprehensive income net of tax	848
Unrealized foreign currency translation gains (losses)
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(1,623)	(1,847)
Adjusted balance, beginning of period	(1,623)
Other comprehensive income (loss) before reclassifications net of tax	80	(1)
Amounts reclassified from accumulated other comprehensive income net of tax	0	0
Other comprehensive income (loss), net of tax	80	(1)
Balance, end of period	(1,543)	(1,848)
Unrealized foreign currency translation gains (losses) | Accounting Standards Update 2019-04
Accumulated Other Comprehensive Income [Roll Forward]
Amounts reclassified from accumulated other comprehensive income net of tax	0
Unrealized gains (losses) on investment securities
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	8,548	4,234
Adjusted balance, beginning of period	9,396
Other comprehensive income (loss) before reclassifications net of tax	(3,359)	2,340
Amounts reclassified from accumulated other comprehensive income net of tax	6	(13)
Other comprehensive income (loss), net of tax	(3,353)	2,327
Balance, end of period	6,043	6,561
Unrealized gains (losses) on investment securities | Accounting Standards Update 2019-04
Accumulated Other Comprehensive Income [Roll Forward]
Amounts reclassified from accumulated other comprehensive income net of tax	848
Unrealized gains (losses) on derivatives
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(33)	(24)
Adjusted balance, beginning of period	(33)
Other comprehensive income (loss) before reclassifications net of tax	(2)	(2)
Amounts reclassified from accumulated other comprehensive income net of tax	0	0
Other comprehensive income (loss), net of tax	(2)	(2)
Balance, end of period	(35)	(26)
Unrealized gains (losses) on derivatives | Accounting Standards Update 2019-04
Accumulated Other Comprehensive Income [Roll Forward]
Amounts reclassified from accumulated other comprehensive income net of tax	0
Pension liability adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(277)	(212)
Adjusted balance, beginning of period	(277)
Other comprehensive income (loss) before reclassifications net of tax	(6)	3
Amounts reclassified from accumulated other comprehensive income net of tax	6	3
Other comprehensive income (loss), net of tax	0	6
Balance, end of period	(277)	$ (206)
Pension liability adjustment | Accounting Standards Update 2019-04
Accumulated Other Comprehensive Income [Roll Forward]
Amounts reclassified from accumulated other comprehensive income net of tax	$ 0

SHAREHOLDERS' EQUITY - Reclassi

SHAREHOLDERS' EQUITY - Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020		Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)		$ 7		$ (17)
Income tax (expense) or benefit		(154)		(314)
Net of tax		$ 566		$ 928
Blended statutory income tax rate		21.40%		25.30%
Reclassification Out Of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax		$ (12)		$ 10
Reclassification Out Of Accumulated Other Comprehensive Income | Unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)		(7)		17
Income tax (expense) or benefit		1	[1]	(4)	[2]
Net of tax		(6)		13
Reclassification Out Of Accumulated Other Comprehensive Income | Pension liability adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Acquisition and operating expenses, actuarial gains (losses)	[3]	(8)		(4)
Acquisition and operating expenses, prior service (cost) credit	[3]	0		0
Income tax (expense) or benefit		2	[1]	1	[2]
Net of tax		$ (6)		$ (3)
[1]	Based on 21% blended tax rate
[2]	Based on 25% blended tax rate
[3]	These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 12 for additional details).

SHARE-BASED COMPENSATION - Addi

SHARE-BASED COMPENSATION - Additional Information (Detail) - USD ($) shares in Thousands, $ in Millions	1 Months Ended	3 Months Ended
	Feb. 29, 2020	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock options exercised		$ 6	$ 17
Tax benefit from exercise of stock options		$ 17	$ 22
Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, maximum number of shares issuable		75,000
Share-based compensation arrangement by share-based payment award, maximum number of shares issuable other than options and stock appreciation rights		38,000
Shares available for future grants under the long-term incentive plan		38,000
Long-term incentive plan awards, term (in years)		10 years
Long-term incentive plan awards, vesting period		3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards		$ 72
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, number, shares		2,566		2,573
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition		2 years 6 months
Restricted stock awards, grants in period		1,376
Performance based Vesting Condition | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards		$ 35
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, number, shares		1,700
Restricted stock awards, grants in period	409

SHARE-BASED COMPENSATION - Stoc

SHARE-BASED COMPENSATION - Stock Options Outstanding and Exercisable (Detail) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / sharesshares
Share-based Payment Arrangement [Abstract]
Options Outstanding - Stock Option Shares | shares	3,354
Options Outstanding - Weighted-Average Remaining Term (Yrs)	4 years 4 months 24 days
Options Outstanding - Aggregate Intrinsic Value | $	$ 16
Options Outstanding - Weighted-Average Exercise Price Per Share | $ / shares	$ 29.98
Options Exercisable - Stock Option Shares | shares	3,353
Options Exercisable - Weighted-Average Remaining Term (Yrs.)	4 years 4 months 24 days
Options Exercisable - Aggregate Intrinsic Value | $	$ 16
Options Exercisable - Weighted-Average Exercise Price Per Share | $ / shares	$ 29.97

SHARE-BASED COMPENSATION - Rest

SHARE-BASED COMPENSATION - Restricted Stock Activity (Details) - Restricted Stock shares in Thousands	3 Months Ended
	Mar. 31, 2020$ / sharesshares
Shares
Beginning Balance | shares	2,573
Granted | shares	1,376
Canceled | shares	(25)
Vested | shares	(1,358)
Ending Balance | shares	2,566
Weighted-Average Grant-Date Fair Value Per Share
Beginning Balance | $ / shares	$ 44.66
Granted | $ / shares	46.66
Cancelled | $ / shares	46.52
Vested | $ / shares	38.48
Ending Balance | $ / shares	$ 48.97

BENEFIT PLANS - Additional Info

BENEFIT PLANS - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amount of years active employees have left to meet rule of 80 in order to be eligible for postretirement medical benefits			5 years
Amount of years left to meet 15 year service requirement for active employees age 55 or older to be eligible for postretirement medical benefits			5 years
Net periodic (benefit) cost, excluding service cost	$ 6	$ 5
Lower Limit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Health care plan, retirement age and years of service combined years for eligibility (rule of 80)			80 years
Health care plan, retirement age for eligibility, (in years)			55 years
Health care plan, number of years of service for eligibility			15 years
Japan | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions	9
U.S. | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions	$ 0

BENEFIT PLANS - Net Periodic (B

BENEFIT PLANS - Net Periodic (Benefit) Cost Included in Acquisition and Operating Expenses (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 0	$ 0
Interest cost	0	0
Expected return on plan assets	0	0
Amortization of net actuarial loss	1	0
Net periodic (benefit) cost	1	0
Japan | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	6	5
Interest cost	1	1
Expected return on plan assets	(2)	(2)
Amortization of net actuarial loss	1	1
Net periodic (benefit) cost	6	5
U.S. | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	7	6
Interest cost	8	9
Expected return on plan assets	(9)	(7)
Amortization of net actuarial loss	6	3
Net periodic (benefit) cost	$ 12	$ 11

COMMITMENTS AND CONTINGENT LI_2

COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
Commitments and Contingencies Disclosure [Abstract]
Loss contingency accrual, insurance-related assessment, discount rate	4.25%
Loss contingency, discounted amount of insurance-related assessment liability	$ 62
Loss contingency, undiscounted amount of insurance-related assessment liability	94
Loss contingency, insurance-related assessment, discounted amount of premium tax offset	48
Loss contingency, insurance-related assessment, undiscounted amount of premium tax offset	74
Loss contingency, loss in period	$ 14

SUBSEQUENT EVENTS - Additional

SUBSEQUENT EVENTS - Additional Information (Detail) - 3.60% senior notes due April 2030 - Subsequent event $ in Billions	1 Months Ended
	Apr. 30, 2020USD ($)
Subsequent Event [Line Items]
Debt instrument, principal amount	$ 1
Debt instrument, interest rate	3.60%
Debt instrument, redemption, description	These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 45 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.