Aflac (AFL) 10-K 26 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 17, 2015	Jun. 30, 2014
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	AFL
Entity Registrant Name	AFLAC INC
Entity Central Index Key	4977
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		438,903,157
Entity Public Float			$27,797,345,404

Consolidated_Statements_of_Ear

Consolidated Statements of Earnings (USD $)	12 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Revenues:
Net Premiums, principally supplemental health insurance	$19,072		$20,135		$22,148
Net investment income	3,319		3,293		3,473
Realized investment gains (losses):
Other-than-temporary impairment losses realized	-31	[1]	-199	[1]	-977	[1]
Sales and redemptions	215		262		474
Derivative and other gains (losses)	31		336		154
Total realized investment gains (losses)	215		399		-349
Other income	122		112		92
Total revenues	22,728		23,939		25,364
Benefits and expenses:
Benefits and claims, net	12,937		13,813		15,330
Acquisition and operating expenses:
Amortization of deferred policy acquisition costs	1,108		1,074		1,117
Insurance commissions	1,436		1,528		1,744
Insurance expenses	2,261		2,222		2,415
Interest expense	317		293		261
Other operating expenses	178		193		195
Total acquisition and operating expenses	5,300		5,310		5,732
Total benefits and expenses	18,237		19,123		21,062
Earnings before income taxes	4,491		4,816		4,302
Income Tax Expense:
Current	1,079		1,236		816
Deferred	461		422		620
Total income tax expense	1,540		1,658		1,436
Net earnings	$2,951		$3,158		$2,866
Net earnings per share:
Basic (in dollars per share)	$6.54		$6.80		$6.14
Diluted (in dollars per share)	$6.50		$6.76		$6.11
Weighted-average outstanding common shares used in computing earnings per share (In thousands):
Basic (in shares)	451,204		464,502		466,868
Diluted (in shares)	454,000		467,408		469,287
[1]	Includes $45 and $597 for the years ended December 31, 2013 and 2012, respectively, for credit-related impairments; $26 and $27 for the years ended December 31, 2013 and 2012, respectively, for impairments due to severity and duration of decline in fair value; and $31, $128 and $353 for the years ended December 31, 2014, 2013 and 2012, respectively, from change in intent to sell securities

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (Loss) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net earnings	$2,951		$3,158		$2,866
Other comprehensive income (loss) before income taxes:
Unrealized foreign currency translation gains (losses) during period	-1,455		-1,588		-287
Unrealized gains (losses) on investment securities:
Unrealized holding gains (losses) on investment securities during period	5,947		-2,362		1,660
Reclassification adjustment for realized (gains) losses on investment securities included in net earnings	-54		-56		497
Unrealized gains (losses) on derivatives during period	-17		-10		-22
Pension liability adjustment during period	-76		157		-20
Total other comprehensive income (loss) before income taxes	4,345		-3,859		1,828
Income tax expense (benefit) related to items of other comprehensive income (loss)	1,803		-581		1,078
Other comprehensive income (loss), net of income taxes	2,542	[1]	-3,278	[1]	750
Total comprehensive income (loss)	$5,493		($120)		$3,616
[1]	All amounts in the table above are net of tax.

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Securities available for sale, at fair value:
Equity securities (cost $19 in 2014 and $17 in 2013)	$28		$21
Securities held to maturity, at amortized cost:
Fixed maturities	34,242		44,415
Other investments	171		463
Cash and cash equivalents	4,658		2,543
Total investments and cash	107,341		108,459
Receivables	842		1,165
Accrued investment income	762		798
Deferred policy acquisition costs	8,273		8,798
Property and equipment, at cost less accumulated depreciation	429		481
Other	2,120	[1]	1,606	[1]
Total assets	119,767		121,307
Policy liabilities:
Future policy benefits	65,646		69,136
Unpaid policy claims	3,630		3,763
Unearned premiums	8,626		10,642
Other policyholders' funds	6,031		5,861
Total policy liabilities	83,933		89,402
Income taxes	5,293		3,718
Payables for return of cash collateral on loaned securities	2,193		5,820
Notes payable	5,282		4,897
Other	4,719	[2]	2,850	[2]
Commitments and contingent liabilities (Note 14)
Total liabilities	101,420		106,687
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2014 and 2013; issued 668,132 shares in 2014 and 667,046 shares in 2013	67		67
Additional paid-in capital	1,711		1,644
Retained earnings	22,156		19,885
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)	-2,541		-1,505
Unrealized gains (losses) on investment securities	4,672		1,035
Unrealized gains (losses) on derivatives	-26		-12
Pension liability adjustment	-126		-81
Treasury stock, at average cost	-7,566		-6,413
Total shareholders' equity	18,347		14,620
Total liabilities and shareholders' equity	119,767		121,307
Investments Other Than Consolidated Variable Interest Entities
Securities available for sale, at fair value:
Fixed maturities	61,407		53,227
Perpetual securities	2,240		2,479
Securities held to maturity, at amortized cost:
Fixed maturities	34,159		44,178
Variable Interest Entity, Consolidated
Securities available for sale, at fair value:
Fixed maturities	4,166		4,843
Perpetual securities	429		468
Securities held to maturity, at amortized cost:
Fixed maturities	$83		$237
[1]	Includes $106 in 2014 and 2013 of derivatives from consolidated variable interest entities
[2]	Includes $318 in 2014 and $207 in 2013 of derivatives from consolidated variable interest entities

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, except Share data in Thousands, unless otherwise specified
Securities available for sale, equity securities, cost	$19	$17
Securities held to maturity, fixed maturities, fair value	38,497	45,846
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)	668,132	667,046
Asset derivatives	802	488
Liability derivatives	2,423	837
Investments Other Than Consolidated Variable Interest Entities
Securities available for sale, fixed maturities, amortized cost	55,365	52,402
Securities available for sale, perpetual securities, amortized cost	2,035	2,524
Securities held to maturity, fixed maturities, fair value	38,413	45,610
Variable Interest Entity, Consolidated
Securities available for sale, fixed maturities, amortized cost	3,020	4,109
Securities available for sale, perpetual securities, amortized cost	405	463
Securities held to maturity, fixed maturities, fair value	84	236
Asset derivatives	106	106
Liability derivatives	$318	$207

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (USD $)	Total	Common stock:	Additional paid-in capital:	Retained earnings:	Accumulated other comprehensive income (loss):	Treasury stock:
In Millions, unless otherwise specified
Balance, beginning of period at Dec. 31, 2011		$66	$1,408	$15,148	$1,965	($5,641)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options		1	31
Share-based compensation			34
Net earnings	2,866			2,866
Dividends to shareholders ($1.50 per share in 2014, $1.42 per share in 2013, and $1.34 per share in 2012)				-627
Unrealized foreign currency translation gains (losses) during period, net of income taxes					-651
Unrealized gains (losses) on investment securities during the period, net of income taxes and reclassification adjustments					1,427
Unrealized gains (losses) on derivatives during period, net of income taxes					-14
Pension liability adjustment during period, net of income taxes					-12
Purchases of treasury stock						-118
Treasury stock reissued			32			63
Balance, end of period at Dec. 31, 2012	15,978	67	1,505	17,387	2,715	-5,696
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options		0	50
Share-based compensation			32
Net earnings	3,158			3,158
Dividends to shareholders ($1.50 per share in 2014, $1.42 per share in 2013, and $1.34 per share in 2012)				-660
Unrealized foreign currency translation gains (losses) during period, net of income taxes					-1,838
Unrealized gains (losses) on investment securities during the period, net of income taxes and reclassification adjustments					-1,535
Unrealized gains (losses) on derivatives during period, net of income taxes					-7
Pension liability adjustment during period, net of income taxes					102
Purchases of treasury stock						-813
Treasury stock reissued			57			96
Balance, end of period at Dec. 31, 2013	14,620	67	1,644	19,885	-563	-6,413
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options		0	29
Share-based compensation			-3
Net earnings	2,951			2,951
Dividends to shareholders ($1.50 per share in 2014, $1.42 per share in 2013, and $1.34 per share in 2012)				-680
Unrealized foreign currency translation gains (losses) during period, net of income taxes					-1,036
Unrealized gains (losses) on investment securities during the period, net of income taxes and reclassification adjustments					3,637
Unrealized gains (losses) on derivatives during period, net of income taxes					-14
Pension liability adjustment during period, net of income taxes					-45
Purchases of treasury stock						-1,210
Treasury stock reissued			41			57
Balance, end of period at Dec. 31, 2014	$18,347	$67	$1,711	$22,156	$1,979	($7,566)

Consolidated_Statements_of_Sha1

Consolidated Statements of Shareholders' Equity (Parenthetical) (Retained earnings:, USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Retained earnings:
Dividends to shareholders (in dollars per share)	$1.50	$1.42	$1.34

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Cash flows from operating activities:
Net earnings	$2,951		$3,158		$2,866
Adjustments to reconcile net earnings to net cash provided by operating activities:
Change in receivables and advance premiums	-7		-8		-199
Increase in deferred policy acquisition costs	-225		-404		-643
Increase in policy liabilities	3,614		6,806		12,005
Change in income tax liabilities	123		993		712
Realized investment (gains) losses	-215		-399		349
Other, net	309		401		-138
Net cash provided (used) by operating activities	6,550		10,547		14,952
Securities available for sale:
Fixed maturities sold	4,178		9,631		7,385
Fixed maturities matured or called	1,001		2,907		1,959
Perpetual securities sold	0		264		1,599
Perpetual securities matured or called	203		256		376
Securities held to maturity:
Fixed maturities matured or called	8,475		6,515		1,859
Costs of investments acquired:
Available for sale fixed maturities acquired	-10,978		-22,967		-19,533
Available-for-sale equity securities acquired	-5		0		0
Held to maturity fixed maturities acquired	-3,564		-6,756		-16,550
Other investments, net	272		-319		-6
Settlement of derivatives, net	-636		-1,624		0
Cash received (pledged or returned) as collateral, net	-3,217		1,037		5,439
Other, net	30		-35		520
Net cash provided (used) by investing activities	-4,241		-11,091		-16,952
Cash flows from financing activities:
Purchases of treasury stock	-1,210		-813		-118
Proceeds from borrowings	750		700		1,506
Principal payments under debt obligations	-335		0		-341
Dividends paid to shareholders	-654		-635		-603
Change in investment-type contracts, net	1,253		1,790		1,457
Treasury stock reissued	33		88		32
Other, net	16		6		12
Net cash provided (used) by financing activities	-147		1,136		1,945
Effect of exchange rate changes on cash and cash equivalents	-47		-90		-153
Net change in cash and cash equivalents	2,115		502		-208
Cash and cash equivalents, beginning of period	2,543		2,041		2,249
Cash and cash equivalents, end of period	4,658		2,543		2,041
Supplemental disclosures of cash flow information:
Income taxes paid	1,416		754		788
Interest paid	241		210		178
Noncash interest	76	[1]	82	[1]	83	[1]
Impairment losses included in realized investment losses	31	[2]	199	[2]	977	[2]
Noncash financing activities:
Capitalized lease obligations	9		0		4
Associate stock bonus
Treasury stock issued for:
Treasury stock issued	35		36		35
Shareholder dividend reinvestment
Treasury stock issued for:
Treasury stock issued	26		25		24
Share-based compensation grants
Treasury stock issued for:
Treasury stock issued	$4		$4		$4
[1]	Consists primarily of accreted interest on discounted advance premiums
[2]	Includes $45 and $597 for the years ended DecemberB 31, 2013 and 2012, respectively, for credit-related impairments; $26 and $27 for the years ended DecemberB 31, 2013 and 2012, respectively, for impairments due to severity and duration of decline in fair value; and $31, $128 and $353 for the years ended DecemberB 31, 2014, 2013 and 2012, respectively, from change in intent to sell securities

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2014
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 and Japan. The Company's insurance business is marketed and administered through American Family Life Assurance Company of Columbus (Aflac), which operates in the United States (Aflac U.S.) and as a branch in Japan (Aflac Japan). American Family Life Assurance Company of New York (Aflac New York) is a wholly owned subsidiary of Aflac. Most of Aflac's policies are individually underwritten and marketed through independent agents. Additionally, Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. Our insurance operations in the United States and our branch in Japan service the two markets for our insurance business. Aflac Japan's revenues, including realized gains and losses on its investment portfolio, accounted for 72% of the Company's total revenues in 2014, compared with 74% in 2013 and 77% in 2012. The percentage of the Company's total assets attributable to Aflac Japan was 82% at December 31, 2014, compared with 85% at December 31, 2013.
	Basis of Presentation
	We prepare our financial statements in accordance with U.S. generally accepted accounting principles (GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to GAAP issued by the FASB are derived from the FASB Accounting Standards CodificationTM (ASC). The preparation of financial statements in conformity with GAAP requires us to make estimates when recording transactions resulting from business operations based on currently available information. The most significant items on our balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments, deferred policy acquisition costs, 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, we believe the amounts provided are adequate.
	The 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.
	Significant Accounting Policies
	Translation of Foreign Currencies: The functional currency of Aflac Japan's insurance operations is the Japanese yen. We translate our yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. We include in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.
	Prior to October 1, 2013, Aflac Japan maintained an investment portfolio of dollar-denominated securities on behalf of Aflac U.S., which served as an economic currency hedge of a portion of our investment in Aflac Japan. The functional currency for these investments was the U.S. dollar. The related investment income and realized/unrealized investment gains and losses were denominated in U.S. dollars. Since the functional currency of this portfolio was the U.S. dollar, there was no translation adjustment to record in other comprehensive income for these investments when the yen/dollar exchange rate changed. The foreign exchange gains and losses related to this portfolio continue to be taxable in Japan and the U.S. when the securities matured or were sold. Until maturity or sale, deferred tax expense or benefit associated with the foreign exchange gains or losses is recognized in income tax expense on other comprehensive income. As of October 1, 2013, these investments were transferred into the Aflac Japan investment portfolio. These investments began to have remeasurement and translation effects recorded in other comprehensive income in the fourth quarter of 2013.
	We have designated a majority of the Parent Company's yen-denominated liabilities (Samurai and Uridashi notes and yen-denominated loans) as non-derivative hedges and designated foreign currency forwards and options as derivative hedges of the foreign currency exposure of our investment in Aflac Japan. Outstanding principal and related accrued interest on these Parent Company liabilities and the fair value of these derivatives are translated into U.S. dollars at end-of-period exchange rates. Currency translation adjustments and changes in the fair value of these derivatives are recorded as unrealized foreign currency translation gains (losses) in other comprehensive income and are included in accumulated other comprehensive income.
	Insurance Revenue and Expense Recognition: The supplemental health and life insurance policies we issue are classified as long-duration contracts. The contract provisions generally cannot be changed or canceled during the contract period; however, we may adjust premiums for supplemental health policies issued in the United States within prescribed guidelines and with the approval of state insurance regulatory authorities.
	Insurance premiums for most of the Company's health and life policies are recognized ratably as earned income over the premium payment periods of the policies. When revenues are reported, the related amounts of benefits and expenses are charged against such revenues, so that profits are recognized in proportion to premium revenues during the period the policies are expected to remain in force. This association is accomplished by means of annual additions to the liability for future policy benefits and the deferral and subsequent amortization of policy acquisition costs.
	Premiums from the Company's products with limited-pay features are collected over a significantly shorter period than the period over which benefits are provided. Premiums for these products are recognized ratably over the scheduled premium payment period. At the policyholder's option, customers can also pay discounted advanced premiums for certain of these products. Advanced premiums are deferred and recognized ratably over the regularly scheduled premium payment period. For the Company's limited-pay products, any gross premium in excess of the net premium is deferred during the scheduled premium payment period and recognized into benefits in a constant relationship with insurance in force. Benefits are recorded as an expense when they are incurred. A liability for future policy benefits is recorded when premiums are recognized using the net premium method.
	The calculation of deferred policy acquisition costs (DAC) and the liability for future policy benefits requires the use of estimates based on sound actuarial valuation techniques. For new policy issues, we review our actuarial assumptions and deferrable acquisition costs each year and revise them when necessary to more closely reflect recent experience and studies of actual acquisition costs. For policies in force, we evaluate DAC by major product groupings to determine that they are recoverable from future revenues, and any amounts determined not to be recoverable are charged against net earnings. We have not had any material charges to earnings for DAC that was determined not to be recoverable in any of the years presented in this Form 10-K.
	Advertising expense is reported as incurred in insurance expenses in the consolidated statements of earnings.
	Cash and Cash Equivalents: Cash and cash equivalents include cash on hand, money market instruments and other debt instruments with a maturity of 90 days or less when purchased.
	Investments: Our debt securities consist of fixed-maturity securities, which are classified as either held to maturity or available for sale. Securities classified as held to maturity are securities that we have the ability and intent to hold to maturity or redemption and are carried at amortized cost. All other fixed-maturity debt securities, our perpetual securities and our equity securities are classified as available for sale and are carried at fair value. If the fair value is higher than the amortized cost for debt and perpetual securities, or the purchase cost for equity securities, the excess is an unrealized gain, and if lower than cost, the difference is an unrealized loss. The net unrealized gains and losses on securities available for sale, plus the unamortized unrealized gains and losses on debt securities transferred to the held-to-maturity portfolio, less related deferred income taxes, are recorded through other comprehensive income and included in accumulated other comprehensive income.
	Amortized cost of debt and perpetual securities is based on our purchase price adjusted for accrual of discount, or amortization of premium, and recognition of impairment charges, if any. The amortized cost of debt and perpetual securities we purchase at a discount or premium will equal the face or par value at maturity or the call date, if applicable. Interest is reported as income when earned and is adjusted for amortization of any premium or discount.
	We have investments in variable interest entities (VIEs). Criteria for evaluating VIEs for consolidation focuses on identifying which enterprise has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. We are the primary beneficiary of certain VIEs. While the VIEs generally operate within a defined set of documents, there are certain powers that are retained by us that are considered significant in our conclusion that we are the primary beneficiary. These powers vary by structure but generally include the initial selection of the underlying collateral or, for collateralized debt obligations (CDOs), the reference credits to include in the structure; the ability to obtain the underlying collateral in the event of default; and the ability to appoint or dismiss key parties in the structure. In particular, our powers surrounding the underlying collateral were the most significant powers since those most significantly impact the economics of the VIE. We have no obligation to provide any continuing financial support to any of the entities in which we are the primary beneficiary. Our maximum loss is limited to our original investment. Neither we nor any of our creditors have the ability to obtain the underlying collateral, nor do we have control over the instruments in the VIEs, unless there is an event of default. For those entities where we are the primary beneficiary, the assets consolidated are fixed-maturity securities, perpetual securities and derivative instruments; collateral is reported separately under the captions fixed maturities- and perpetual securities- consolidated variable interest entities on our balance sheet.
	For the collateralized mortgage obligations (CMOs) held in our fixed-maturity securities portfolio, we recognize income using a constant effective yield, which is based on anticipated prepayments and the estimated economic life of the securities. When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The net investment in CMO securities is adjusted to the amount that would have existed had the new effective yield been applied at the time of acquisition. This adjustment is reflected in net investment income.
	We use the specific identification method to determine the gain or loss from securities transactions and report the realized gain or loss in the consolidated statements of earnings. Securities transactions are accounted for based on values as of the trade date of the transaction.
	An investment in a fixed maturity or perpetual security is impaired if the fair value falls below book value. We regularly review our entire investment portfolio for declines in value. The majority of our investments are evaluated for other-than-temporary impairment using our debt impairment model. Our debt impairment model focuses on the ultimate collection of the cash flows from our investments. The determination of the amount of impairments under this model is based upon our periodic evaluation and assessment of known and inherent risks associated with the respective securities. Such evaluations and assessments are revised as conditions change and new information becomes available.
	The determination of whether an impairment in value is other than temporary is based largely on our evaluation of the issuer's creditworthiness. Our team of experienced credit professionals must apply considerable judgment in determining the likelihood of the security recovering in value while we own it. Factors that may influence this include the overall level of interest rates, credit spreads, the credit quality of the underlying issuer, and other factors. This process requires consideration of risks which can be controlled to a certain extent, such as credit risk, and risks which cannot be controlled, such as interest rate risk.
	If, after monitoring and analyses, management believes that fair value will not recover to amortized cost prior to the disposal of the security, we recognize an other-than-temporary impairment of the security. Once a security is considered to be other-than-temporarily impaired, the impairment loss is separated into two separate components: the portion of the impairment related to credit and the portion of the impairment related to factors other than credit. We automatically recognize a charge to earnings for the credit-related portion of other-than-temporary impairments. Impairments related to factors other than credit are charged to earnings in the event we intend to sell the security prior to the recovery of its amortized cost or if it is more likely than not that we would be required to dispose of the security prior to recovery of its amortized cost; otherwise, non-credit-related other-than-temporary impairments are charged to other comprehensive income.
	Our investments in perpetual securities that are rated below investment grade are evaluated for other-than-temporary impairment under our equity impairment model. Our equity impairment model focuses on the severity of a security's decline in fair value coupled with the length of time the fair value of the security has been below amortized cost and the financial condition and near-term prospects of the issuer.
	We lend fixed-maturity securities to financial institutions in short-term security lending transactions. These securities continue to be carried as investment assets on our balance sheet during the terms of the loans and are not reported as sales. We receive cash or other securities as collateral for such loans. For loans involving unrestricted cash or securities as collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral.
	Other investments include policy loans and other short-term investments with maturities of one year or less, but greater than 90 days, at the time of purchase and are stated at amortized cost, which approximates estimated fair value.
	Derivatives and Hedging: Freestanding derivative instruments are reported in the consolidated balance sheet at fair value and are reported in other assets and other liabilities, with changes in value reported in earnings and/or other comprehensive income. These freestanding derivatives are interest rate swaps, foreign currency swaps, credit default swaps (CDSs), foreign currency forwards, foreign currency options, and options on interest rate swaps (or interest rate swaptions). Interest rate and foreign currency swaps are used within VIEs to hedge the risk arising from interest rate and currency exchange risk, while the CDSs are used to increase the yield and improve the diversification of the portfolio. Foreign currency forwards and options are used in hedging foreign exchange risk on U.S. dollar-denominated securities in Aflac Japan's portfolio. Foreign currency forwards and options are used to hedge certain portions of forecasted cash flows denominated in yen. Interest rate swaps are used to hedge the variability of interest cash flows associated with our variable interest rate notes, and cross-currency interest rate swaps, also referred to as foreign currency swaps, are used to economically convert certain dollar-denominated note obligations into yen-denominated principal and interest obligations. Interest rate swaptions are used to hedge interest rate risk for certain U.S. dollar-denominated available-for-sale securities. We do not use derivatives for trading purposes, nor do we engage in leveraged derivative transactions.
	From time to time, we purchase certain investments that contain an embedded derivative. We assess whether this embedded derivative is clearly and closely related to the asset that serves as its host contract. If we deem that the embedded derivative's terms are not clearly and closely related to the host contract, and a separate instrument with the same terms would qualify as a derivative instrument, the derivative is separated from that contract, held at fair value and reported with the host instrument in the consolidated balance sheet, with changes in fair value reported in earnings. If we have elected the fair value option, the embedded derivative is not bifurcated, and the entire investment is held at fair value with changes in fair value reported in earnings.
	For those relationships where we seek hedge accounting, we formally document all relationships between hedging instruments and hedged items, as well as our risk-management objectives and strategies for undertaking various hedge transactions. This process includes linking derivatives and nonderivatives that are designated as hedges to specific assets or liabilities on the balance sheet. We also assess, both at inception and on an ongoing basis, whether the derivatives and nonderivatives used in hedging activities are highly effective in offsetting changes in fair values or cash flows of the hedged items. The assessment of hedge effectiveness determines the accounting treatment of noncash changes in fair value.
	Changes in the fair value of any of our derivatives that are designated and qualify as cash flow hedges are recorded in other comprehensive income as long as they are deemed effective. Any hedge ineffectiveness is recorded immediately in current period earnings within derivative and other gains (losses). Periodic derivative net coupon settlements are recorded in the line item of the consolidated statements of earnings in which the cash flows of the hedged item are recorded.
	Changes in the estimated fair value of derivative instruments that are designated and qualify as fair value hedges, including amounts measured as ineffectiveness, and changes in the estimated fair value of the hedged item related to the designated risk being hedged, are reported in current earnings within derivative and other gains (losses).
	We have designated the majority of the Parent Company's yen-denominated liabilities (Samurai and Uridashi notes and yen-denominated loans) as nonderivative hedges and designated derivatives as hedges of the foreign currency exposure to our investment in Aflac Japan. At the beginning of each quarter, we make our net investment hedge designation. If the total of the designated Parent Company non-derivative and derivatives notional is equal to or less than our net investment in Aflac Japan, the hedge is deemed to be effective, and the exchange effect on the yen-denominated liabilities and the change in estimated fair value of the derivatives are reported in the unrealized foreign currency component of other comprehensive income. Should these designated net investment hedge positions exceed our net investment in Aflac Japan, the foreign exchange effect on the portion that exceeds our investment in Aflac Japan would be recognized in current earnings within derivative and other gains (losses).
	Derivatives that are not designated as hedges are carried at fair value with all changes in fair value recorded in current period earnings within derivative and other gains (losses). We include the fair value of all freestanding derivatives in either other assets or other liabilities on the balance sheet.
	We receive and pledge cash or other securities as collateral on open derivative positions. Cash received as collateral is reported as an asset with a corresponding liability for the return of the collateral. Cash pledged as collateral is recorded as a reduction to cash, and a corresponding receivable is recognized for the return of the cash collateral. We generally can repledge or resell collateral obtained by us, although we do not typically exercise such rights. Securities received as collateral are not recognized unless we were to exercise our right to sell that collateral or exercise remedies on that collateral upon a counterparty default. Securities that we have pledged as collateral continue to be carried as investment assets on our balance sheet.
	Deferred Policy Acquisition Costs: Certain direct and incremental costs of acquiring new business are deferred and amortized with interest over the premium payment periods in proportion to the ratio of annual premium income to total anticipated premium income. Anticipated premium income is estimated by using the same mortality, persistency and interest assumptions used in computing liabilities for future policy benefits. In this manner, the related acquisition expenses are matched with revenues. Deferred costs include the excess of current-year commissions over ultimate renewal-year commissions and certain incremental direct policy issue, underwriting and sales expenses. All of these incremental costs are directly related to successful policy acquisition.
	For some products, policyholders can elect to modify product benefits, features, rights or coverages by exchanging a contract for a new contract or by amendment, endorsement, or rider to a contract, or by the election of a feature or coverage within a contract. These transactions are known as internal replacements. For internal replacement transactions where the resulting contract is substantially unchanged, the policy is accounted for as a continuation of the replaced contract. Unamortized deferred acquisition costs from the original policy continue to be amortized over the expected life of the new policy, and the costs of replacing the policy are accounted for as policy maintenance costs and expensed as incurred. Internal replacement transactions that result in a policy that is not substantially unchanged are accounted for as an extinguishment of the original policy and the issuance of a new policy. Unamortized deferred acquisition costs on the original policy that was replaced are immediately expensed, and the costs of acquiring the new policy are capitalized and amortized in accordance with our accounting policies for deferred acquisition costs.
	We measure the recoverability of DAC and the adequacy of our policy reserves annually by performing gross premium valuations on our business. Our testing indicates that our DAC is recoverable and our policy liabilities are adequate. (See the following discussion for further information regarding policy liabilities.)
	Policy Liabilities: Future policy benefits represent claims that are expected to occur in the future and are computed by a net level premium method using estimated future investment yields, persistency and recognized morbidity and mortality tables modified to reflect our experience, including a provision for adverse deviation. These assumptions are generally established at the time a policy is issued.
	Unpaid policy claims are estimates computed on an undiscounted basis using statistical analyses of historical claims experience adjusted for current trends and changed conditions. The ultimate liability may vary significantly from such estimates. We regularly adjust these estimates as new claims experience emerges and reflect the changes in operating results in the year such adjustments are made.
	Other policy liabilities consist primarily of discounted advance premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as premium revenue over the contractual premium payment period.
	For internal replacements that are determined to not be substantially unchanged, policy liabilities related to the original policy that was replaced are immediately released, and policy liabilities are established for the new insurance contract.
	Reinsurance: We enter into reinsurance agreements with other companies in the normal course of business. For each of our reinsurance agreements, we determine if 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, benefits and DAC are reported net of insurance ceded. See Note 8 of the Notes to the Consolidated Financial Statements for additional information.
	Income Taxes: Income tax provisions are generally based on pretax earnings reported for financial statement purposes, which differ from those amounts used in preparing our income tax returns. Deferred income taxes are recognized for temporary differences between the financial reporting basis and income tax basis of assets and liabilities, based on enacted tax laws and statutory tax rates applicable to the periods in which we expect the temporary differences to reverse. We record deferred tax assets for tax positions taken based on our assessment of whether the tax position is more likely than not to be sustained upon examination by taxing authorities. A valuation allowance is established for deferred tax assets when it is more likely than not that an amount will not be realized.
	As discussed in the Translation of Foreign Currencies section above, Aflac Japan maintains certain dollar-denominated investments that, prior to October 1, 2013, did not have any foreign currency translation adjustments recognized in other comprehensive income. However, the deferred tax expense or benefit associated with foreign exchange gains or losses on these investments is recognized in other comprehensive income (loss) until the securities mature or are sold. Total income tax expense (benefit) related to items of other comprehensive income (loss) included a deferred tax expense of $614 million in 2013 and $492 million in 2012 for these dollar-denominated investments. Excluding these amounts from total taxes on other comprehensive income would result in an effective income tax rate on pretax other comprehensive income (loss) of 31% in 2013 and 32% in 2012.
	Policyholder Protection Corporation and State Guaranty Association Assessments: In Japan, the government has required the insurance industry to contribute to a policyholder protection corporation. We recognize a charge for our estimated share of the industry's obligation once it is determinable. We review the estimated liability for policyholder protection corporation contributions on an annual basis and report any adjustments in Aflac Japan's expenses.
	In the United States, each state has a guaranty association that supports insolvent insurers operating in those states. To date, our state guaranty association assessments have not been material.
	Treasury Stock: Treasury stock is reflected as a reduction of shareholders' equity at cost. We use the weighted-average purchase cost to determine the cost of treasury stock that is reissued. We include any gains and losses in additional paid-in capital when treasury stock is reissued.
	Share-Based Compensation: We measure compensation cost related to our share-based payment transactions at fair value on the grant date, and we recognize those costs in the financial statements over the vesting period during which the employee provides service in exchange for the award.
	Earnings Per Share: We compute basic earnings per share (EPS) by dividing net earnings by the weighted-average number of unrestricted shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the weighted-average number of shares outstanding for the period plus the shares representing the dilutive effect of share-based awards.
	Reclassifications: Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. Components of our deferred inventory were reclassified to separately reflect deferred foreign currency gains and losses which were previously apportioned to each component of the deferred inventory, see Note 10 of the Notes to the Consolidated Financial Statements. These reclassifications had no impact on net earnings or total shareholders' equity.
	New Accounting Pronouncements
	Recently Adopted Accounting Pronouncements
	Presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists: In July 2013, the FASB issued guidance to amend the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The new guidance essentially states that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. However, to the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. This accounting standard applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists at the reporting date. This guidance is effective for annual reporting periods beginning on or after December 15, 2013, and interim periods within those annual periods and requires prospective presentation for all comparative periods presented. We adopted this guidance as of January 1, 2014. The adoption of this guidance did not have a significant impact on our financial statements.
	Derivatives and hedging: In July 2013, the FASB issued an update which allows entities to use the Federal Funds Effective Swap Rate, also referred to as the Overnight Index Swap Rate (OIS), as a benchmark interest rate for hedge accounting purposes. Previously the only acceptable benchmark rates for hedge accounting purposes under GAAP were U.S. Treasury rates and the London Interbank Offered Rate (LIBOR) swap rate. This update reflects the evolution of market hedging practices and is intended to provide more flexibility for hedge accounting purposes. We adopted this guidance in the third quarter of 2013 on a prospective basis for qualifying new or redesignated hedging relationships entered into on or after the effective date of July 17, 2013. The adoption of the guidance had no impact on our financial position or results of operations.
	Reporting of amounts reclassified out of accumulated other comprehensive income: In February 2013, the FASB issued guidance that requires reclassification adjustments for items that are reclassified out of accumulated other comprehensive income to net income to be presented in statements where the components of net income and the components of other comprehensive income are presented or in the footnotes to the financial statements. Additionally, the amendment requires cross-referencing to other disclosures currently required for other reclassification items. We adopted this guidance as of January 1, 2013. The adoption of this guidance impacted our financial statement disclosures, but it did not have an impact on our financial position or results of operations.
	Disclosures about offsetting assets and liabilities: In December 2011, the FASB issued guidance to amend the disclosure requirements about offsetting assets and liabilities. The new guidance essentially clarifies the FASB's intent concerning the application of existing offsetting disclosure requirements. Entities are required to disclose gross and net information about both instruments and transactions eligible for offset in the statement of financial position and instruments and transactions when those activities are subject to an agreement similar to a master netting arrangement. The scope of this guidance was clarified and revised in January 2013 to apply to derivatives, repurchase agreements, reverse repurchase agreements, securities borrowing and securities lending arrangements. The objective of this disclosure is to move toward consistency between U.S. GAAP and International Financial Reporting Standards (IFRS). We adopted this guidance as of January 1, 2013. The adoption of this guidance impacted our financial statement disclosures, but it did not have an impact on our financial position or results of operations.
	Fees paid to the federal government by health insurers: In July 2011, the FASB issued guidance on the accounting for fees owed by health insurers as mandated by the Patient Protection and Affordable Care Act as amended by the Health Care and Education Reconciliation Act (the Acts). The Acts impose an annual fee on health insurers for each calendar year beginning on or after January 1, 2014. A health insurer's portion of the annual fee is payable by September 30 of the applicable calendar year once the entity provides health insurance for any U.S. health risk in that year. The annual fee for the health insurance industry will be allocated to individual health insurers based on the ratio of the amount of an entity's net premiums written during the preceding calendar year to the amount of health insurance for any U.S. health risk that is written during the preceding calendar year. The accounting guidance specifies that the liability for the fee should be estimated and recorded in full in the applicable calendar year in which the fee is payable with a corresponding deferred cost that is amortized to expense using a straight-line method of allocation unless another method better allocates the fee over the calendar year that it is payable. This guidance is effective for calendar years beginning after December 31, 2013. We adopted this guidance as of January 1, 2014. The adoption of this guidance did not have a significant impact on our financial position or results of operations.
	Presentation of comprehensive income: In June 2011, the FASB issued guidance to amend the presentation of comprehensive income. The amendment requires that all non-owner changes in shareholders' equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. We adopted this guidance as of January 1, 2012 and elected the option to report comprehensive income in two separate but consecutive statements. The adoption of this guidance did not have an impact on our financial position or results of operations.
	Fair value measurements and disclosures: In May 2011, the FASB issued guidance to amend the fair value measurement and disclosure requirements. Most of the amendments are clarifications of the FASB's intent about the application of existing fair value measurement and disclosure requirements. Other amendments change a particular principle or requirement for measuring fair value or disclosing information about fair value measurements. The new fair value measurement disclosures include additional quantitative and qualitative disclosures for Level 3 measurements, including a qualitative sensitivity analysis of fair value to changes in unobservable inputs, and categorization by fair value hierarchy level for items for which the fair value is only disclosed. We adopted this guidance as of January 1, 2012. The adoption of this guidance impacted our financial statement disclosures, but it did not affect our financial position or results of operations.
	Accounting for costs associated with acquiring or renewing insurance contracts: In October 2010, the FASB issued amended accounting guidance on accounting for costs associated with acquiring or renewing insurance contracts. Under the previous guidance, costs that varied with and were primarily related to the acquisition of a policy were deferrable. Under the amended guidance, only incremental direct costs associated with the successful acquisition of a new or renewal contract may be capitalized, and direct-response advertising costs may be capitalized only if they meet certain criteria. This guidance is effective on a prospective or retrospective basis for interim and annual periods beginning after December 15, 2011. We retrospectively adopted this guidance as of January 1, 2012. The retrospective adoption of this accounting standard resulted in an after-tax cumulative reduction to retained earnings of $391 million and an after-tax cumulative reduction to unrealized foreign currency translation gains in accumulated other comprehensive income of $67 million, resulting in a total reduction to shareholders' equity of $458 million as of December 31, 2009, the opening balance sheet date in the period of adoption. The adoption of this accounting standard had an immaterial impact on net income in 2011 and all preceding years.
	Accounting Pronouncements Pending Adoption
	Derivatives and Hedging - Determining whether the host contract in a hybrid financial instrument issued in the form of a share is more akin to debt or equity: In November 2014, the FASB issued guidance to clarify how to evaluate the economic characteristics and risks of a host contract in a hybrid financial instrument that is issued in the form of a share. The guidance also clarifies that an entity should assess the substance of the relevant terms and features when considering how to weight those terms and features. The guidance is effective for annual periods and interim periods beginning after December 15, 2015. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Presentation of Financial Statements - Going Concern - Disclosure of uncertainties about an entity’s ability to continue as a going concern: In August 2014, the FASB issued this amendment that provides U.S. GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. The amendment is effective for annual periods ending after December 15, 2016, and interim periods within annual periods beginning after December 15, 2016. Early application is permitted for annual or interim reporting periods for which the financial statements have not previously been issued. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Receivables - Troubled debt restructurings by creditors - classification of certain government-guaranteed mortgage loans upon foreclosure: In August 2014, the FASB issued updated guidance for troubled debt restructurings affecting creditors that hold government-guaranteed mortgage loans, including those guaranteed by the FHA and the VA. The guidance requires that a mortgage loan be derecognized and a separate other receivable be recognized upon foreclosure if certain conditions are met. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Compensation - Stock Compensation - Accounting for share-based payments when the terms of an award provide that a performance target could be achieved after the requisite service period: In June 2014, the FASB issued this amendment that provides guidance on certain share-based payment awards that require a specific performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. A reporting entity should apply existing guidance to awards with performance conditions that affect vesting to account for such awards. The performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. The guidance is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. Early adoption is permitted. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Transfers and Servicing, Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures: In June 2014, the FASB issued updated guidance for repurchase agreement and security lending transactions to change the accounting for repurchase-to-maturity transactions and linked repurchase financings to be accounted for as secured borrowings, consistent with the accounting for other repurchase agreements. The amendments also require new disclosures to increase transparency about the types of collateral pledged in repurchase agreements and similar transactions accounted for as secured borrowings. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Revenue from contracts with customers: In May 2014, the FASB issued updated guidance that affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (e.g., insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The amendments are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Receivables - Troubled debt restructurings by creditors - Reclassification of residential real estate collateralized consumer mortgage loans upon foreclosure: In January 2014, the FASB issued updated guidance for troubled debt restructurings clarifying when an in substance repossession or foreclosure occurs, and when a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
Recent accounting guidance not discussed above is not applicable, did not have, or is not expected to have a material impact to our business.

BUSINESS_SEGMENT_AND_FOREIGN_I

BUSINESS SEGMENT AND FOREIGN INFORMATION	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
BUSINESS SEGMENT INFORMATION	BUSINESS SEGMENT AND FOREIGN 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. Operating business segments that are not individually reportable and business activities not included in Aflac Japan or Aflac U.S. are included in the "Other business segments" category.
	We do not allocate corporate overhead expenses to business segments. We evaluate and manage our business segments using a financial performance measure called pretax operating earnings. Our definition of operating earnings includes interest cash flows associated with notes payable and excludes the following items from net earnings on an after-tax basis: realized investment gains/losses (securities transactions, impairments, and the impact of derivative and hedging activities), nonrecurring items and other non-operating income (loss). We then exclude income taxes related to operations to arrive at pretax operating earnings. Information regarding operations by segment for the years ended December 31 follows:
	(In millions)	2014					2013					2012
	Revenues:
	Aflac Japan:
	Net earned premiums:
	Cancer		$	5,596				$	6,123				$	7,537
	Medical and other health		3,770					4,282					5,244
	Life insurance		4,495					4,577					4,370
	Net investment income		2,662					2,651					2,845
	Other income		32					55					57
	Total Aflac Japan		16,555					17,688					20,053
	Aflac U.S.:
	Earned premiums:
	Accident/disability		2,303					2,284					2,213
	Cancer		1,279					1,283					1,282
	Other health		1,371					1,334					1,259
	Life insurance		258					252					242
	Net investment income		645					632					613
	Other income		3					6					19
	Total Aflac U.S.		5,859					5,791					5,628
	Other business segments		43					49					46
	Total business segment revenues		22,457					23,528					25,727
	Realized investment gains (losses)		171			(1)		389			(1)		(349		)
	Corporate		281					302					269
	Intercompany eliminations		(248		)			(308		)			(276		)
	Other non-operating income (loss)		67					28					(7		)
	Total revenues		$	22,728				$	23,939				$	25,364
	(1) Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations
	(In millions)	2014					2013					2012
	Pretax earnings:
	Aflac Japan		$	3,458				$	3,628				$	3,904
	Aflac U.S.		1,073					1,038					997
	Other business segments		(2		)			(1		)			(3		)
	Total business segment pretax operating earnings		4,529					4,665					4,898
	Interest expense, noninsurance operations		(198		)			(198		)			(184		)
	Corporate and eliminations		(78		)			(68		)			(56		)
	Pretax operating earnings		4,253					4,399					4,658
	Realized investment gains (losses)		171			(1)		389			(1)		(349		)
	Other non-operating income (loss)		67					28					(7		)
	Total earnings before income taxes		$	4,491				$	4,816				$	4,302
	Income taxes applicable to pretax operating earnings		$	1,456				$	1,512				$	1,561
	Effect of foreign currency translation on operating earnings		(117		)			(357		)			8
	(1) Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations
	Assets as of December 31 were as follows:
	(In millions)	2014					2013					2012
	Assets:
	Aflac Japan		$	98,525				$	102,973				$	113,678
	Aflac U.S.		18,383					16,112					16,122
	Other business segments		128					155					154
	Total business segment assets		117,036					119,240					129,954
	Corporate		24,636					19,909					20,318
	Intercompany eliminations		(21,905		)			(17,842		)			(19,178		)
	Total assets		$	119,767				$	121,307				$	131,094
	Yen-Translation Effects: The following table shows the yen/dollar exchange rates used for or during the periods ended December 31. Exchange effects were calculated using the same yen/dollar exchange rate for the current year as for each respective prior year.
		2014					2013					2012
	Statements of Earnings:
	Weighted-average yen/dollar exchange rate		105.46					97.54					79.81
	Yen percent strengthening (weakening)		(7.5		)%			(18.2		)%			(.1		)%
	Exchange effect on pretax operating earnings (in millions)		$	(180	)			$	(534	)			$	11
		2014					2013
	Balance Sheets:
	Yen/dollar exchange rate at December 31		120.55					105.39
Yen percent strengthening (weakening)		(12.6		)%			(17.8		)%
Exchange effect on total assets (in millions)		$	(10,706	)			$	(17,836	)
Exchange effect on total liabilities (in millions)		(12,025		)			(19,806		)
Transfers of funds from Aflac Japan: Aflac Japan makes payments to the Parent Company for management fees and to Aflac U.S. for allocated expenses and profit repatriations. Information on transfers for each of the years ended December 31 is shown below. See Note 13 for information concerning restrictions on transfers from Aflac Japan.
(In millions)	2014					2013					2012
Management fees		$	39				$	37				$	30
Allocated expenses		71					74					58
Profit repatriation		1,704					771					422
Total transfers from Aflac Japan		$	1,814				$	882				$	510
Property and Equipment: The costs of buildings, furniture and equipment are depreciated principally on a straight-line basis over their estimated useful lives (maximum of 50 years for buildings and 20 years for furniture and equipment). Expenditures for maintenance and repairs are expensed as incurred; expenditures for betterments are capitalized and depreciated. Classes of property and equipment as of December 31 were as follows:
(In millions)	2014					2013
Property and equipment:
Land		$	168				$	168
Buildings		393					444
Equipment and furniture		305					329
Total property and equipment		866					941
Less accumulated depreciation		437					460
Net property and equipment		$	429				$	481
Receivables: Receivables consist primarily of monthly insurance premiums due from individual policyholders or their employers for payroll deduction of premiums, net of an allowance for doubtful accounts. At December 31, 2014, $386 million, or 45.8% of total receivables, were related to Aflac Japan's operations, compared with $731 million, or 82.9%, at December 31, 2013.

INVESTMENTS

INVESTMENTS	12 Months Ended
	Dec. 31, 2014
Investments [Abstract]
INVESTMENTS	INVESTMENTS
	Net Investment Income
	The components of net investment income for the years ended December 31 were as follows:
	(In millions)	2014						2013						2012
	Fixed-maturity securities		$	3,249					$	3,210					$	3,248
	Perpetual securities		141						153						253
	Equity securities and other		7						7						17
	Short-term investments and cash equivalents		2						1						2
	Gross investment income		3,399						3,371						3,520
	Less investment expenses		80						78						47
	Net investment income		$	3,319					$	3,293					$	3,473
	Investment Holdings
	The amortized cost for our investments in debt and perpetual securities, the cost for equity securities and the fair values of these investments at December 31 are shown in the following tables.
		2014
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	17,341					$	1,740					$	0					$	19,081
	Municipalities		88						9						0						97
	Mortgage- and asset-backed securities		351						35						0						386
	Public utilities		1,691						226						5						1,912
	Sovereign and supranational		799						163						0						962
	Banks/financial institutions		2,752						325						189						2,888
	Other corporate		3,479						531						48						3,962
	Total yen-denominated		26,501						3,029						242						29,288
	Dollar-denominated:
	U.S. government and agencies		100						17						0						117
	Municipalities		961						201						2						1,160
	Mortgage- and asset-backed securities		185						31						0						216
	Public utilities		5,061						960						36						5,985
	Sovereign and supranational		343						111						0						454
	Banks/financial institutions		2,943						775						8						3,710
	Other corporate		22,291						2,682						330						24,643
	Total dollar-denominated		31,884						4,777						376						36,285
	Total fixed maturities		58,385						7,806						618						65,573
	Perpetual securities:
	Yen-denominated:
	Banks/financial institutions		2,132						223						92						2,263
	Other corporate		183						48						0						231
	Dollar-denominated:
	Banks/financial institutions		125						50						0						175
	Total perpetual securities		2,440						321						92						2,669
	Equity securities		19						9						0						28
	Total securities available for sale		$	60,844					$	8,136					$	710					$	68,270
		2014
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities held to maturity, carried at amortized cost:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	20,023					$	3,195					$	0					$	23,218
	Municipalities		346						71						0						417
	Mortgage- and asset-backed securities		43						3						0						46
	Public utilities		3,342						281						20						3,603
	Sovereign and supranational		2,556						272						14						2,814
	Banks/financial institutions		4,932						231						78						5,085
	Other corporate		3,000						326						12						3,314
	Total yen-denominated		34,242						4,379						124						38,497
	Total securities held to maturity		$	34,242					$	4,379					$	124					$	38,497
		2013
(In millions)	Cost or						Gross						Gross						Fair
	Amortized						Unrealized						Unrealized						Value
	Cost						Gains						Losses
Securities available for sale, carried at fair value:
Fixed maturities:
Yen-denominated:
Japan government and agencies		$	14,936					$	431					$	33					$	15,334
Mortgage- and asset-backed securities		558						29						0						587
Public utilities		2,261						100						18						2,343
Sovereign and supranational		978						85						28						1,035
Banks/financial institutions		2,799						220						242						2,777
Other corporate		3,956						151						185						3,922
Total yen-denominated		25,488						1,016						506						25,998
Dollar-denominated:
U.S. government and agencies		92						10						4						98
Municipalities		992						71						12						1,051
Mortgage- and asset-backed securities		163						21						0						184
Public utilities		4,931						471						183						5,219
Sovereign and supranational		404						85						1						488
Banks/financial institutions		3,318						447						33						3,732
Other corporate		21,123						1,347						1,170						21,300
Total dollar-denominated		31,023						2,452						1,403						32,072
Total fixed maturities		56,511						3,468						1,909						58,070
Perpetual securities:
Yen-denominated:
Banks/financial institutions		2,582						151						217						2,516
Other corporate		209						0						0						209
Dollar-denominated:
Banks/financial institutions		196						35						9						222
Total perpetual securities		2,987						186						226						2,947
Equity securities		17						5						1						21
Total securities available for sale		$	59,515					$	3,659					$	2,136					$	61,038
	2013
(In millions)	Cost or						Gross						Gross						Fair
	Amortized						Unrealized						Unrealized						Value
	Cost						Gains						Losses
Securities held to maturity, carried at amortized cost:
Fixed maturities:
Yen-denominated:
Japan government and agencies		$	27,362					$	1,347					$	1					$	28,708
Municipalities		399						41						0						440
Mortgage- and asset-backed securities		58						3						0						61
Public utilities		3,900						150						122						3,928
Sovereign and supranational		2,941						171						72						3,040
Banks/financial institutions		6,310						146						328						6,128
Other corporate		3,445						183						87						3,541
Total yen-denominated		44,415						2,041						610						45,846
Total securities held to maturity		$	44,415					$	2,041					$	610					$	45,846
The methods of determining the fair values of our investments in fixed-maturity securities, perpetual securities and equity securities are described in Note 5.
During 2014, we reclassified three investments from the held-to-maturity portfolio to the available-for-sale portfolio as a result of the issuers being downgraded to below investment grade. At the time of the transfer, the securities had an aggregate amortized cost of $424 million and an aggregate unrealized loss of $54 million. During 2013, we reclassified two investments from the held-to-maturity portfolio to the available-for-sale portfolio as a result of the issuer being downgraded to below investment grade. At the time of the transfer, the securities had an aggregate amortized cost of $492 million and an aggregate unrealized loss of $153 million. During 2012, we reclassified seven investments from the held-to-maturity portfolio to the available-for-sale portfolio as a result of the issuers being downgraded to below investment grade. At the time of the transfer, the securities had an aggregate amortized cost of $1.2 billion and an aggregate unrealized loss of $290 million.
Contractual and Economic Maturities
The contractual maturities of our investments in fixed maturities at December 31, 2014, were as follows:
	Aflac Japan												Aflac U.S.
(In millions)	Amortized						Fair						Amortized						Fair
	Cost						Value						Cost						Value
Available for sale:
Due in one year or less		$	369					$	390					$	65					$	69
Due after one year through five years		1,519						1,771						628						724
Due after five years through 10 years		10,351						10,979						1,472						1,561
Due after 10 years		34,018						38,595						9,103						10,540
Mortgage- and asset-backed securities		405						461						36						46
Total fixed maturities available for sale		$	46,662					$	52,196					$	11,304					$	12,940
Held to maturity:
Due after one year through five years		1,520						1,631						0						0
Due after five years through 10 years		1,937						2,130						0						0
Due after 10 years		30,742						34,690						0						0
Mortgage- and asset-backed securities		43						46						0						0
Total fixed maturities held to maturity		$	34,242					$	38,497					$	0					$	0
At December 31, 2014, the Parent Company had a portfolio of available-for-sale fixed-maturity securities totaling $419 million at amortized cost and $437 million at fair value, which is not included in the table above.
Expected maturities may differ from contractual maturities because some issuers have the right to call or prepay obligations with or without call or prepayment penalties.
The majority of our perpetual securities are subordinated to other debt obligations of the issuer, but rank higher than the issuer's equity securities. Perpetual securities have characteristics of both debt and equity investments, along with unique features that create economic maturity dates for the securities. Although perpetual securities have no contractual maturity date, they have stated interest coupons that were fixed at their issuance and subsequently change to a floating short-term interest rate after some period of time. The instruments are generally callable by the issuer at the time of changing from a fixed coupon rate to a new variable rate of interest, which is determined by the combination of some market index plus a fixed amount of basis points. The net effect is to create an expected economic maturity date for the instrument. The economic maturities of our investments in perpetual securities, which were all reported as available for sale at December 31, 2014, were as follows:
	Aflac Japan												Aflac U.S.
(In millions)	Amortized						Fair						Amortized						Fair
	Cost						Value						Cost						Value
Due in one year or less		$	306					$	300					$	5					$	5
Due after one year through five years		624						674						0						0
Due after 10 years		1,466						1,635						39						55
Total perpetual securities available for sale		$	2,396					$	2,609					$	44					$	60
Investment Concentrations
Our investment process begins with an independent approach to underwriting each issuer's fundamental credit quality. We evaluate independently those factors which we believe could influence an issuer's ability to make payments under the contractual terms of our 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). We further evaluate 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 as of December 31 were as follows:
	2014						2013
(In millions)	Credit		Amortized		Fair		Credit		Amortized		Fair
	Rating		Cost		Value		Rating		Cost		Value
Japan National Government(1)	A		$37,021		$41,878		AA		$41,924		$43,619
(1)JGBs or JGB-backed securities
Banks and Financial Institutions
One of our largest investment sector concentrations as of December 31, 2014, was banks and financial institutions. Within the countries we approve for investment opportunities, we primarily invest in financial institutions that are strategically crucial to each approved country's economy. The bank and financial institution sector is a highly regulated industry and plays a strategic role in the global economy.
Our total investments in the bank and financial institution sector as of December 31, including those classified as perpetual securities, were as follows:
	2014											2013
	Total Investments in						Percentage of					Total Investments in						Percentage of
	Banks and Financial						Total Investment					Banks and Financial						Total Investment
	Institutions Sector						Portfolio					Institutions Sector						Portfolio
	(in millions)											(in millions)
Fixed maturities:
Amortized cost		$	10,627					11	%				$	12,427					12	%
Fair value		11,683						11					12,637						12
Perpetual securities:
Upper Tier II:
Amortized cost		$	1,554					2	%				$	1,920					2	%
Fair value		1,645						1					1,913						2
Tier I:
Amortized cost		703						1					858						1
Fair value		793						1					825						1
Total:
Amortized cost		$	12,884					14	%				$	15,205					15	%
Fair value		14,121						13					15,375						15
Realized Investment Gains and Losses
Information regarding pretax realized gains and losses from investments for the years ended December 31 follows:
(In millions)	2014				2013				2012
Realized investment gains (losses) on securities:
Fixed maturities:
Available for sale:
Gross gains from sales	$	192			$	316			$	427
Gross losses from sales	(12		)		(87		)		(48		)
Net gains (losses) from redemptions	34				34				2
Other-than-temporary impairment losses	(31		)		(128		)		(734		)
Held to maturity:
Net gains (losses) from redemptions	1				0				4
Total fixed maturities	184				135				(349		)
Perpetual securities:
Available for sale:
Gross gains from sales	0				0				127
Gross losses from sales	0				(1		)		(98		)
Net gains (losses) from redemptions	0				0				60
Other-than-temporary impairment losses	0				(70		)		(243		)
Total perpetual securities	0				(71		)		(154		)
Equity securities:
Other-than-temporary impairment losses	0				(1		)		0
Total equity securities	0				(1		)		0
Derivatives and other:
Derivative gains (losses)	31				326				151
Other	0				10				3
Total derivatives and other	31				336				154
Total realized investment gains (losses)	$	215			$	399			$	(349	)
Other-than-temporary Impairment
The fair values of our debt and perpetual security investments fluctuate based on changes in interest rates, foreign exchange, and credit spreads in the global financial markets. Fair values can also be heavily influenced by the values of the assets of the issuer and expected ultimate recovery values upon a default, bankruptcy or other financial restructuring. Credit spreads are most impacted by the general credit environment and global market liquidity. Interest rates are driven by numerous factors including, but not limited to, supply and demand, governmental monetary actions, expectations of inflation and economic growth. We believe that fluctuations in the fair values of our investment securities related to general changes in the level of credit spreads or interest rates have little bearing on underlying credit quality of the issuer, and whether our investment is ultimately recoverable. Generally, we consider such declines in fair values to be temporary even in situations where an investment remains in an unrealized loss position for a year or more.
However, in the course of our credit review process, we may determine that it is unlikely that we will recover our investment in an issuer due to factors specific to an individual issuer, as opposed to general changes in global credit spreads or interest rates. In this event, we consider such a decline in the investment's fair value, to the extent it is below the investment's cost or amortized cost, to be an other-than-temporary impairment of the investment and reduce the book value of the investment to its fair value.
In addition to the usual investment risk associated with a debt instrument, our perpetual security holdings are largely issued by banks that are integral to the financial markets of the sovereign country of the issuer. As a result of the issuer's position within the economy of the sovereign country, our perpetual securities may be subject to a higher risk of nationalization of their issuers in connection with capital injections from an issuer's sovereign government. We cannot be assured that such capital support will extend to all levels of an issuer's capital structure. In addition, certain governments or regulators may consider imposing interest and principal payment restrictions on issuers of hybrid securities to preserve cash and preserve the issuer's capital. Beyond the cash flow impact that additional deferrals would have on our portfolio, such deferrals could result in ratings downgrades of the affected securities, which in turn could result in a reduction of fair value of the securities and increase our regulatory capital requirements. We consider these factors in our credit review process.
When determining our intention to sell a security prior to recovery of its fair value to amortized cost, we evaluate facts and circumstances such as, but not limited to, future cash flow needs, decisions to reposition our security portfolio, and risk profile of individual investment holdings. We perform ongoing analyses of our liquidity needs, which includes cash flow testing of our policy liabilities, debt maturities, projected dividend payments and other cash flow and liquidity needs. Our cash flow testing includes extensive duration analysis of our investment portfolio and policy liabilities. Based on our analyses, we have concluded that we have sufficient excess cash flows to meet our liquidity needs without selling any of our investments prior to their maturity.
The following table details our pretax other-than-temporary impairment losses by investment category that resulted from our impairment evaluation process for the years ended December 31.
(In millions)	2014				2013				2012
Perpetual securities	$	0			$	70			$	243
Corporate bonds	31				102				345
Mortgage- and asset-backed securities	0				0				3
Sovereign and supranational	0				26				386
Equity securities	0				1				0
Total other-than-temporary impairment losses realized (1)	$	31			$	199			$	977
(1) Includes $45 and $597 for the years ended December 31, 2013 and 2012, respectively, for credit-related impairments;
$26 and $27 for the years ended December 31, 2013 and 2012, respectively, for impairments due to severity and duration
of decline in fair value; and $31, $128 and $353 for the years ended December 31, 2014, 2013 and 2012, respectively, from change
in intent to sell securities
Unrealized Investment Gains and Losses
Information regarding changes in unrealized gains and losses from investments for the years ended December 31 follows:
(In millions)	2014						2013						2012
Changes in unrealized gains (losses):
Fixed maturities:
Available for sale		$	5,629					$	(2,281	)				$	1,624
Transferred to held to maturity		(10		)				(9		)				(14		)
Perpetual securities:
Available for sale		269						(129		)				547
Equity securities		5						1						0
Total change in unrealized gains (losses)		$	5,893					$	(2,418	)				$	2,157
Effect on Shareholders' Equity
The net effect on shareholders' equity of unrealized gains and losses from investment securities at December 31 was as follows:
(In millions)	2014						2013
Unrealized gains (losses) on securities available for sale		$	7,426					$	1,523
Unamortized unrealized gains on securities transferred to held to maturity		0						11
Deferred income taxes		(2,754		)				(499		)
Shareholders’ equity, unrealized gains (losses) on investment securities		$	4,672					$	1,035
Gross Unrealized Loss Aging
The following tables show the fair values and gross unrealized losses of our available-for-sale and held-to-maturity investments 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 at December 31.
	2014
	Total												Less than 12 months											12 months or longer
(In millions)	Fair						Unrealized						Fair						Unrealized					Fair					Unrealized
	Value						Losses						Value						Losses					Value					Losses
Fixed Maturities:
Municipalities:
Dollar-denominated		75						2						53						1					22					1
Public utilities:
Dollar-denominated		1,001						36						164						7					837					29
Yen-denominated		805						25						98						1					707					24
Sovereign and supranational:
Yen-denominated		359						14						0						0					359					14
Banks/financial institutions:
Dollar-denominated		205						8						53						5					152					3
Yen-denominated		1,828						267						166						0					1,662					267
Other corporate:
Dollar-denominated		8,072						330						1,901						62					6,171					268
Yen-denominated		1,151						60						122						2					1,029					58
Total fixed maturities		13,496						742						2,557						78					10,939					664
Perpetual securities:
Yen-denominated		783						92						194						5					589					87
Total perpetual securities		783						92						194						5					589					87
Total		$	14,279					$	834					$	2,751					$	83				$	11,528				$	751
	2013
	Total												Less than 12 months											12 months or longer
(In millions)	Fair						Unrealized						Fair						Unrealized					Fair					Unrealized
	Value						Losses						Value						Losses					Value					Losses
Fixed Maturities:
Japan government and agencies:
Yen-denominated		$	8,869					$	34					$	8,869					$	34				$	0				$	0
Municipalities:
Dollar-denominated		177						12						145						8					32					4
Public utilities:
Dollar-denominated		2,023						183						1,740						143					283					40
Yen-denominated		2,519						140						1,816						54					703					86
Sovereign and supranational:
Dollar-denominated		12						1						12						1					0					0
Yen-denominated		1,152						100						791						34					361					66
Banks/financial institutions:
Dollar-denominated		547						33						454						23					93					10
Yen-denominated		4,533						570						2,322						107					2,211					463
Other corporate:
Dollar-denominated		11,588						1,170						8,504						733					3,084					437
Yen-denominated		3,372						272						2,296						152					1,076					120
U.S. government and agencies:
Dollar-denominated		36						4						36						4					0					0
Total fixed maturities		34,828						2,519						26,985						1,293					7,843					1,226
Perpetual securities:
Dollar-denominated		59						9						52						8					7					1
Yen-denominated		1,322						217						748						74					574					143
Total perpetual securities		1,381						226						800						82					581					144
Equity securities		5						1						5						1					0					0
Total		$	36,214					$	2,746					$	27,790					$	1,376				$	8,424				$	1,370
Analysis of Securities in Unrealized Loss Positions
The unrealized losses on our 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, we perform a more focused review of the related issuers' credit profile. For corporate issuers, we evaluate their assets, business profile including industry dynamics and competitive positioning, financial statements and other available financial data. For non-corporate issuers, we analyze all sources of credit support, including issuer-specific factors. We utilize information available in the public domain and, for certain private placement issuers, from consultations with the issuers directly. We also consider ratings from Nationally Recognized Statistical Rating Organizations (NRSROs), as well as the specific characteristics of the security we own including seniority in the issuer's capital structure, covenant predictions, or other relevant features. From these reviews, we evaluate the issuers' continued ability to service our investment through payment of interest and principal.
The following table provides more information on our unrealized loss position as of December 31.
	2014												2013
(In millions)	Investments				Gross				Gross				Investments				Gross				Gross
	in an Unrealized				Unrealized				Unrealized				in an Unrealized				Unrealized				Unrealized
	Loss Position				Losses				Losses that are Investment Grade				Loss Position				Losses				Losses that are Investment Grade
Fixed Maturities:
Japan government		0	%			0	%			0	%			25	%			1	%			100	%
and agencies
Public utilities		13				7				100				13				12				98
Sovereign and		3				2				100				3				4				100
supranational
Banks/financial		14				33				31				14				22				64
institutions
Other corporate		65				47				88				41				53				91
Total fixed		95	%			89	%							96	%			92	%
maturities
Perpetual securities		5				11				100				4				8				90
Total		100	%			100	%							100	%			100	%
Assuming no credit-related factors, as investments near maturity, unrealized gains and losses are expected to diminish. Based on our credit analysis, we believe that the issuers of our investments in the sectors shown in the table above have the ability to service their obligations to us.
Perpetual Securities
The majority of our investments in Upper Tier II and Tier I perpetual securities are in highly-rated global financial institutions. Upper Tier II securities have more debt-like characteristics than Tier I securities and are senior to Tier I securities, preferred stock, and common equity of the issuer. Conversely, Tier I securities have more equity-like characteristics, but are senior to the common equity of the issuer, and they may also be senior to certain preferred shares; depending on the individual security; the issuer's capital structure and the regulatory jurisdiction of the issuer.
Details of our holdings of perpetual securities as of December 31 were as follows:
Perpetual Securities
			2014																		2013
(In millions)	Credit		Amortized						Fair						Unrealized						Amortized					Fair					Unrealized
	Rating		Cost						Value						Gain (Loss)						Cost					Value					Gain (Loss)
Upper Tier II:
	A			$	61					$	87					$	26					$	145				$	183				$	38
	BBB			1,330						1,333						3						1,563					1,532					(31		)
	BB or lower			163						225						62						212					198					(14		)
Total Upper Tier II				1,554						1,645						91						1,920					1,913					(7		)
Tier I:
	BBB			519						556						37						746					706					(40		)
	BB or lower			184						237						53						112					119					7
Total Tier I				703						793						90						858					825					(33		)
Other subordinated
- non-banks:
	BB or lower			183						231						48						209					209					0
Total				$	2,440					$	2,669					$	229					$	2,987				$	2,947				$	(40	)
Assuming no credit-related factors develop, as investments near maturity, the unrealized gains or losses are expected to diminish. Based on our credit analysis, we believe that the issuers of our investments in these sectors have the ability to service their obligations to us.
Variable Interest Entities (VIEs)
As a condition to our involvement or investment in a VIE, we enter into certain protective rights and covenants that preclude changes in the structure of the VIE that would alter the creditworthiness of our investment or our beneficial interest in the VIE.
Our involvement with all of the VIEs in which we have an interest is passive in nature, and we are not the arranger of these entities. We have not been involved in establishing these entities, except as it relates to our review and evaluation of the structure of these VIEs in the normal course of our investment decision-making process. Further, we are not, nor have we been, required to purchase any securities issued in the future by these VIEs.
Our ownership interest in the VIEs is limited to holding the obligations issued by them. All of the VIEs in which we invest are static with respect to funding and have no ongoing forms of funding after the initial funding date. We have no direct or contingent obligations to fund the limited activities of these VIEs, nor do we have any direct or indirect financial guarantees related to the limited activities of these VIEs. We have not provided any assistance or any other type of financing support to any of the VIEs we invest in, nor do we have any intention to do so in the future. The weighted-average lives of our notes are very similar to the underlying collateral held by these VIEs where applicable.
Our risk of loss related to our interests in any of our VIEs is limited to our investment in the debt securities issued by them.
VIEs - Consolidated
The following table presents the amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported as of December 31.
Investments in Consolidated Variable Interest Entities
	2014												2013
(In millions)	Amortized						Fair						Amortized						Fair
	Cost						Value						Cost						Value
Assets:
Fixed maturities, available for sale		$	3,020					$	4,166					$	4,109					$	4,843
Perpetual securities, available for sale		405						429						463						468
Fixed maturities, held to maturity		83						84						237						236
Other assets		106						106						106						106
Total assets of consolidated VIEs		$	3,614					$	4,785					$	4,915					$	5,653
Liabilities:
Other liabilities		$	318					$	318					$	207					$	207
Total liabilities of consolidated VIEs		$	318					$	318					$	207					$	207
We are substantively the only investor in the consolidated VIEs listed in the table above. As the sole investor in these VIEs, we have the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and are therefore considered to be the primary beneficiary of the VIEs that we consolidate. We also participate in substantially all of the variability created by these VIEs. The activities of these VIEs are limited to holding debt and perpetual securities and interest rate, foreign currency, and/or CDSs, as appropriate, and utilizing the cash flows from these securities to service our investment. Neither we nor any of our 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, we are not a direct counterparty to the swap contracts and have no control over them. Our loss exposure to these VIEs is limited to our original investment. Our 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 our investment in senior secured bank loans through unit trust structures, the underlying collateral assets and funding of our consolidated VIEs are generally static in nature and the underlying collateral and the reference corporate entities covered by any CDS contracts were all investment grade at the time of issuance.
We are exposed to credit losses within any consolidated CDOs that could result in principal losses to our investments. We have mitigated our risk of credit loss through the structure of the VIE, which contractually requires the subordinated tranches within these VIEs to absorb the majority of the expected losses from the underlying credit default swaps. We currently own only senior mezzanine CDO tranches. Based on our statistical analysis models and the current subordination levels in our CDOs, each of these VIEs can sustain a reasonable number of defaults in the underlying reference entities in the CDSs with no loss to our investment.
VIEs - Not Consolidated
The table below reflects the amortized cost, fair value and balance sheet caption in which our investment in VIEs not consolidated are reported as of December 31.
Investments in Variable Interest Entities Not Consolidated
	2014												2013
(In millions)	Amortized						Fair						Amortized						Fair
	Cost						Value						Cost						Value
Assets:
Fixed maturities, available for sale		$	6,104					$	6,937					$	6,724					$	6,916
Perpetual securities, available for sale		324						330						370						378
Fixed maturities, held to maturity		2,564						2,829						2,949						3,039
Total investments in VIEs not consolidated		$	8,992					$	10,096					$	10,043					$	10,333
The VIEs that we are 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 international capital markets. The variable interests created by these VIEs are principally or solely a result of the debt instruments issued by them. We do not have the power to direct the activities that most significantly impact the entity's economic performance, nor do we have (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. As such, we are not the primary beneficiary of these VIEs and are therefore not required to consolidate them. These VIE investments comprise securities from 191 separate issuers with an average credit rating of BBB.
Securities Lending and Pledged Securities
We lend fixed-maturity securities to financial institutions in short-term security-lending transactions. These short-term security-lending arrangements increase investment income with minimal risk. Our security lending policy requires that the fair value of the securities and/or unrestricted cash received as collateral be 102% or more of the fair value of the loaned securities. The following table presents our security loans outstanding and the corresponding collateral held as of December 31:
(In millions)		2014						2013
Security loans outstanding, fair value		$	2,149					$	5,656
Cash collateral on loaned securities		2,193						5,820
Certain fixed-maturity securities have been pledged as collateral as part of derivative transactions. For additional information regarding pledged securities related to derivative transactions, see Note 4.
At December 31, 2014, debt securities with a fair value of $13 million were on deposit with regulatory authorities in
the United States (including U.S. territories) and Japan. We retain ownership of all securities on deposit and receive the related investment income.
For general information regarding our investment accounting policies, see Note 1.

DERIVATIVE_INSTRUMENTS

DERIVATIVE INSTRUMENTS	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS
	Our freestanding derivative financial instruments consist of: (1) foreign currency swaps, credit default swaps, and interest rate swaps that are associated with investments in special-purpose entities, including VIEs where we are the primary beneficiary; (2) foreign currency forwards and options used in hedging foreign exchange risk on U.S. dollar-denominated securities in Aflac Japan's portfolio; (3) foreign currency forwards and options used to hedge certain portions of forecasted cash flows denominated in yen; (4) swaps associated with our notes payable, consisting of an interest rate swap for our variable interest rate yen-denominated debt and cross-currency interest rate swaps, also referred to as foreign currency swaps, associated with certain senior notes and our subordinated debentures; and (5) options on interest rate swaps (or interest rate swaptions) and futures used to hedge interest rate risk for certain available-for-sale securities. We do not use derivative financial instruments for trading purposes, nor do we engage in leveraged derivative transactions. Some of our derivatives are designated as cash flow hedges, fair value hedges or net investment hedges; however, other derivatives do not qualify for hedge accounting. We utilize a net investment hedge to mitigate foreign exchange exposure resulting from our net investment in Aflac Japan. In addition to designating derivatives as hedging instruments, we have designated the majority of our yen-denominated Samurai and Uridashi notes and yen-denominated loans as nonderivative hedging instruments for this net investment hedge.
	Derivative Types
	We enter into foreign currency swaps pursuant to which we exchange an initial principal amount in one currency for an initial principal amount of another currency, with an agreement to re-exchange the currencies at a future date at an agreed upon exchange rate. 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 our Aflac Japan portfolio to convert foreign-denominated cash flows to yen, the functional currency of Aflac Japan, in order to minimize cash flow fluctuations. We also use foreign currency swaps to economically convert certain of our dollar-denominated senior note and subordinated debenture principal and interest obligations into yen-denominated obligations.
	Foreign currency forwards and options with short-term maturities are executed for the Aflac Japan segment in order to hedge the currency risk on the fair value of certain fixed-maturity dollar-denominated securities. 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 a fixed amount of U.S. dollar put options and sell U.S. dollar call options. The combination of these two actions results in no net premium being paid (i.e. a costless or zero-cost collar). The foreign currency forwards and options are used in fair value hedging relationships to mitigate the foreign exchange risk associated with dollar-denominated investments supporting yen-denominated liabilities.
	Foreign currency forwards and options are also used 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 future date. In the option transactions, we 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 results in no net premium being paid (i.e. a costless or zero-cost collar). Aflac also enters into foreign currency options that give it the right, but not the obligation, to sell yen and buy U.S. dollars at specified future dates at contracted prices.
	Our CDSs are used to assume credit risk related to an individual security or an index. The only CDS derivatives that we have entered into relate to components of certain of our investments in VIEs. These CDS contracts entitle the consolidated VIE to receive periodic fees in exchange for an obligation to compensate the derivative counterparties should the reference security issuers experience a credit event, as defined in the contract.
	Interest rate swaps involve the periodic exchange of cash flows with other parties, at specified intervals, calculated using agreed upon rates or other financial variables and notional principal amounts. Typically, at the time a swap is entered into, the cash flow streams exchanged by the counterparties are equal in value. No cash or principal payments are exchanged at the inception of the contract. Interest rate swaps are primarily used to convert interest receipts on floating-rate fixed-maturity securities contracts to fixed rates. These derivatives are predominantly used to better match cash receipts from assets with cash disbursements required to fund liabilities.
	Interest rate swaptions are options on interest rate swaps. Interest rate collars are combinations of two swaption positions and are executed in order to hedge certain dollar-denominated available-for-sale securities that are held in the Aflac Japan segment. We use collars to protect against significant changes in the fair value associated with interest rate changes of our dollar-denominated available-for-sale securities. In order to maximize the efficiency of the collars while minimizing cost, we set the strike price on each collar so that the premium paid for the ‘payer leg’ is offset by the premium received for having sold the ‘receiver leg’.
	Periodically, depending on general economic conditions, we may enter into other derivative transactions.
	Credit Risk Assumed through Derivatives
	For the interest rate, foreign currency, and credit default swaps associated with our VIE investments for which we are the primary beneficiary, we bear the risk of foreign exchange or interest rate loss due to counterparty default even though we are not a direct counterparty to those contracts. We are a direct counterparty to the interest rate and foreign currency swaps that we have entered into in connection with certain of our senior notes, subordinated debentures, and Samurai notes; foreign currency forwards; foreign currency options; and interest rate swaptions, and therefore we are exposed to credit risk in the event of nonperformance by the counterparties in those contracts. The risk of counterparty default for our VIE swaps, foreign currency swaps, certain foreign currency forwards, foreign currency options and interest rate swaptions is mitigated by collateral posting requirements the counterparties to those transactions must meet. As of December 31, 2014, there were 16 counterparties to our derivative agreements, with five comprising 80% of the aggregate notional amount. The counterparties to these derivatives are financial institutions with the following credit ratings as of December 31:
		2014															2013
	(In millions)	Notional Amount					Asset Derivatives					Liability Derivatives					Notional Amount					Asset Derivatives					Liability Derivatives
		of Derivatives					Fair Value					Fair Value					of Derivatives					Fair Value					Fair Value
	Counterparties' credit rating:
	AA		$	1,098				$	39				$	(36	)			$	161				$	1				$	(7	)
	A		22,564					763					(2,387		)			22,314					487					(830		)
	Total		$	23,662				$	802				$	(2,423	)			$	22,475				$	488				$	(837	)
	We engage in derivative transactions directly with unaffiliated third parties under International Swaps and Derivative Association, Inc. (ISDA) agreements and other documentation. Most of the ISDA agreements also include Credit Support Annex (CSA) provisions, which generally provide for two-way collateral postings, in certain cases at the first dollar of exposure and in other cases once various rating and exposure threshold levels are triggered. We mitigate 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 or that additional collateral be posted upon the occurrence of certain events or circumstances. In addition, a significant portion of the derivative transactions have provisions that require collateral to be posted upon a downgrade of our long-term debt ratings or give the counterparty the right to terminate the transaction upon a downgrade of Aflac’s financial strength rating. The actual amount of collateral required to be posted to counterparties in the event of such downgrades, or the aggregate amount of payments that we 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.
	Collateral posted by us to third parties for derivative transactions was $1.6 billion at December 31, 2014, which consisted entirely of pledged securities, compared with $8 million at December 31, 2013, which consisted of $7 million of pledged securities and $1 million of cash. This collateral 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 $2.1 billion and $18 million as of December 31, 2014 and 2013, respectively. If the credit-risk-related contingent features underlying these agreements had been triggered on December 31, 2014, we estimate that we would be required to post a maximum of $482 million of additional collateral to these derivative counterparties. Collateral obtained by us from third parties for derivative transactions was $619 million and $295 million at December 31, 2014 and 2013, respectively. We generally can repledge or resell collateral obtained by us, although we do not typically exercise such rights.
	Certain of our consolidated VIEs have credit default swap contracts that require them to assume credit risk from an asset pool. Those consolidated VIEs will receive periodic payments based on an agreed upon rate and notional amount and will only make a payment by delivery of associated collateral, which consists of highly rated asset-backed securities, if there is a credit event. A credit event payment will typically be equal to the notional value of the swap contract less the value of the referenced obligations. A credit event is generally defined as a default on contractually obligated interest or principal payments or bankruptcy of the referenced entity. The diversified portfolios of corporate issuers are established within sector concentration limits.
	The following tables present the maximum potential risk, fair value, weighted-average years to maturity, and underlying referenced credit obligation type for credit default swaps within consolidated VIE structures as of December 31.
	2014
			Less than								One to								Three to								Five to								Total
			one year								three years								five years								ten years
	(In millions)	Credit	Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum			Estimated
		Rating	potential				fair value				potential				fair value				potential				fair value				potential				fair value				potential			fair value
			risk								risk								risk								risk								risk
	Index exposure:
	Corporate bonds:
		A	$	0			$	0			$	0			$	0			$	(83	)		$	0			$	0			$	0			$	(83	)	$	0
	Total		$	0			$	0			$	0			$	0			$	(83	)		$	0			$	0			$	0			$	(83	)	$	0
	2013
			Less than								One to								Three to								Five to								Total
			one year								three years								five years								ten years
	(In millions)	Credit	Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum			Estimated
		Rating	potential				fair value				potential				fair value				potential				fair value				potential				fair value				potential			fair value
			risk								risk								risk								risk								risk
	Index exposure:
	Corporate bonds:
		A	$	0			$	0			$	(112	)		$	1			$	0			$	0			$	0			$	0			$	(112	)	$	1
		BBB	0				0				0				0				0				0				(95		)		(4		)		(95		)	(4		)
	Total		$	0			$	0			$	(112	)		$	1			$	0			$	0			$	(95	)		$	(4	)		$	(207	)	$	(3	)
	Accounting for Derivative Financial Instruments
	Freestanding derivatives are carried in our consolidated balance sheets either as assets within other assets or as liabilities within other liabilities at estimated fair value. See Note 5 for a discussion on how we determine the fair value of our derivatives. Accruals on derivatives are recorded in accrued investment income or within other liabilities in the consolidated balance sheets.
	If a derivative is not designated as an accounting hedge or its use in managing risk does not qualify for hedge accounting, changes in the estimated fair value of the derivative are generally reported within derivative and other gains(losses), which is a component of realized investment gains (losses). The fluctuations in estimated fair value of derivatives that have not been designated for hedge accounting can result in volatility in net earnings.
	Hedge Documentation and Effectiveness Testing
	To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated risk of the hedged item. At the inception of the hedging relationship, we formally document all relationships between hedging instruments and hedged items, as well as our risk-management objective and strategy for undertaking each hedge transaction. We document the designation of each hedge as either (i) a hedge of the variability of cash flows to be received or paid related to a recognized asset or liability or the hedge of a forecasted transaction ("cash flow hedge"); (ii) a hedge of the estimated fair value of a recognized asset or liability ("fair value hedge"); or (iii) a hedge of a net investment in a foreign operation. The documentation process includes linking derivatives and nonderivatives that are designated as hedges to specific assets or groups of assets or liabilities on the statement of financial position or to specific forecasted transactions and defining the effectiveness and ineffectiveness testing methods to be used. At the hedge's inception and on an ongoing quarterly basis, we also formally assess whether the derivatives that are used in hedging transactions have been, and are expected to continue to be, highly effective in offsetting their designated risk. Hedge effectiveness is assessed using qualitative and quantitative methods.
	For assessing hedge effectiveness of cash flow hedges, qualitative methods may include the comparison of critical terms of the derivative to the hedged item, and quantitative methods include regression or other statistical analysis of changes in cash flows associated with the hedge relationship. Hedge ineffectiveness of the hedge relationships is measured each reporting period using the “Hypothetical Derivative Method.” For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is reported as a component of other comprehensive income (loss) and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. Gains and losses on the derivative representing hedge ineffectiveness are recognized in current earnings within derivative and other gains (losses). All components of each derivative's gain or loss are included in the assessment of hedge effectiveness.
	For assessing hedge effectiveness of fair value hedges, qualitative methods may include the comparison of critical terms of the derivative to the hedged item, and quantitative methods include regression or other statistical analysis of changes in cash flows associated with the hedge relationship. Hedge ineffectiveness of the hedge relationships is measured each reporting period using the dollar offset method. For derivative instruments that are designated and qualify as fair value hedges, changes in the estimated fair value of the derivative, including amounts measured as ineffectiveness, and changes in the estimated fair value of the hedged item related to the designated risk being hedged, are reported in current earnings within derivative and other gains (losses).
	For the hedge of our net investment in Aflac Japan, we have designated Parent Company yen-denominated liabilities as non-derivative hedging instruments and have designated certain foreign currency forwards and options as derivative hedging instruments. We make our net investment hedge designation at the beginning of each quarter. For assessing hedge effectiveness of net investment hedges, if the total of the designated Parent Company non-derivative and derivatives notional is equal to or less than our net investment in Aflac Japan, the hedge is deemed to be effective. If the hedge is effective, the related exchange effect on the yen-denominated liabilities is reported in the unrealized foreign currency component of other comprehensive income. For derivatives designated as net investment hedges, Aflac follows the forward-rate method. According to that method, all changes in fair value, including changes related to the forward-rate component of foreign currency forward contracts and the time value of foreign currency options, are reported in the unrealized foreign currency component of other comprehensive income. Should these designated net investment hedge positions exceed our net investment in Aflac Japan, the foreign exchange effect on the portion that exceeds our investment in Aflac Japan would be recognized in current earnings within derivative and other gains (losses).
	Discontinuance of Hedge Accounting
	We discontinue hedge accounting prospectively when (1) it is determined that the derivative is no longer highly effective in offsetting changes in the estimated cash flows or fair value of a hedged item; (2) the derivative is de-designated as a hedging instrument; or (3) the derivative expires or is sold, terminated or exercised.
	When hedge accounting is discontinued on a cash flow hedge or fair value hedge, the derivative is carried in the consolidated balance sheets at its estimated fair value, with changes in estimated fair value recognized in current period earnings. For discontinued cash flow hedges, including those where the derivative is sold, terminated or exercised, amounts previously deferred in other comprehensive income (loss) are reclassified into earnings when earnings are impacted by the cash flow of the hedged item.
	Derivative Balance Sheet Classification
	The tables below summarize the balance sheet classification of our derivative fair value amounts, as well as the gross asset and liability fair value amounts, at December 31. The fair value amounts presented do not include income accruals. The notional amount of derivative contracts represents the basis upon which pay or receive amounts are calculated. Notional amounts are not reflective of credit risk.
		2014
	(In millions)	Net Derivatives												Asset						Liability
														Derivatives						Derivatives
	Hedge Designation/ Derivative Type	Notional						Fair Value						Fair Value						Fair Value
		Amount
	Cash flow hedges:
	Foreign currency swaps		$	75					$	(15	)				$	0					$	(15	)
Total cash flow hedges		75						(15		)				0						(15		)
Fair value hedges:
Foreign currency forwards		12,388						(1,791		)				0						(1,791		)
Foreign currency options		697						(32		)				0						(32		)
Interest rate swaptions		2,502						(159		)				0						(159		)
Total fair value hedges		15,587						(1,982		)				0						(1,982		)
Net investment hedge:
Foreign currency forwards		1,307						54						56						(2		)
Total net investment hedge		1,307						54						56						(2		)
Non-qualifying strategies:
Foreign currency swaps		5,765						443						746						(303		)
Credit default swaps		83						0						0						0
Foreign currency forwards		784						(119		)				0						(119		)
Foreign currency options		53						(1		)				0						(1		)
Interest rate swaptions		8						(1		)				0						(1		)
Total non-qualifying strategies		6,693						322						746						(424		)
Total derivatives		$	23,662					$	(1,621	)				$	802					$	(2,423	)
Balance Sheet Location
Other assets		$	6,531					$	802					$	802					$	0
Other liabilities		17,131						(2,423		)				0						(2,423		)
Total derivatives		$	23,662					$	(1,621	)				$	802					$	(2,423	)
	2013
(In millions)	Net Derivatives												Asset						Liability
													Derivatives						Derivatives
Hedge Designation/ Derivative Type	Notional						Fair Value						Fair Value						Fair Value
	Amount
Cash flow hedges:
Foreign currency swaps		$	75					$	3					$	3					$	0
Interest rate swaps		52						0						0						0
Total cash flow hedges		127						3						3						0
Fair value hedges:
Foreign currency forwards		11,249						(582		)				0						(582		)
Interest rate swaptions		4,500						(12		)				20						(32		)
Total fair value hedges		15,749						(594		)				20						(614		)
Net investment hedge:
Foreign currency forwards		356						17						17						0
Foreign currency options		95						3						4						(1		)
Total net investment hedge		451						20						21						(1		)
Non-qualifying strategies:
Foreign currency swaps		5,829						224						442						(218		)
Credit default swaps		207						(3		)				1						(4		)
Interest rate swaps		112						1						1						0
Total non-qualifying strategies		6,148						222						444						(222		)
Total derivatives		$	22,475					$	(349	)				$	488					$	(837	)
Balance Sheet Location
Other assets		$	5,308					$	488					$	488					$	0
Other liabilities		17,167						(837		)				0						(837		)
Total derivatives		$	22,475					$	(349	)				$	488					$	(837	)
Cash Flow Hedges
Certain of our consolidated VIEs have foreign currency swaps that qualify for hedge accounting treatment. For those that have qualified, we have designated the derivative 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). We expect to continue this hedging activity for a weighted-average period of approximately 11 years. The remaining derivatives in our consolidated VIEs that have not qualified for hedge accounting have been designated as held for other investment purposes (“non-qualifying strategies”).
We had an interest rate swap agreement related to 5.5 billion yen variable interest rate Samurai notes that we issued in July 2011 and redeemed in July 2014 (see Note 9). By entering into this contract, we swapped the variable interest rate to a fixed interest rate of 1.475%. We had designated this interest rate swap as a hedge of the variability in our interest cash flows associated with the variable interest rate Samurai notes.
Fair Value Hedges
We designate and account for certain foreign currency forwards and options as fair value hedges when they meet the requirements for hedge accounting. These foreign currency forwards and options hedge the foreign currency exposure of certain dollar-denominated fixed maturity securities within the investment portfolio of our Aflac Japan segment. We recognize gains and losses on these derivatives and the related hedged items in current earnings within derivative and other gains (losses). 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 excluded from the assessment of hedge effectiveness.
We designate and account for interest rate swaptions as fair value hedges when they meet the requirements for hedge accounting. These interest rate swaptions hedge the interest rate exposure of certain dollar-denominated fixed maturity securities within the investment portfolio of our Aflac Japan segment. We recognize gains and losses on these derivatives and the related hedged items in current earnings within derivative and other gains (losses). The change in the fair value of the interest rate swaptions related to the time value of the option is excluded from the assessment of hedge effectiveness.
The following table presents the gains and losses on derivatives and the related hedged items in fair value hedges for the years ended December 31.
Fair Value Hedging Relationships
(In millions)			Hedging Derivatives												Hedged Items
Hedging Derivatives	Hedged Items		Total				Gains (Losses)				Gains (Losses)				Gains (Losses)				Ineffectiveness
			Gains (Losses)				Excluded from Effectiveness Testing				Included in Effectiveness Testing								Recognized for Fair Value Hedge
2014:00:00
Foreign currency forwards	Fixed-maturity securities		$	(1,835	)		$	(38	)		$	(1,797	)		$	1,819			$	22
Foreign currency options	Fixed-maturity securities		(41		)		(4		)		(37		)		38				1
Interest rate	Fixed-maturity securities		(318		)		(36		)		(282		)		316				34
swaptions
2013:00:00
Foreign currency	Fixed-maturity securities		$	(1,735	)		$	(25	)		$	(1,710	)		$	1,700			$	(10	)
forwards
Interest rate	Fixed-maturity securities		17				17				0				0				0
swaptions
2012:00:00
Foreign currency	Fixed-maturity securities		$	(535	)		$	(8	)		$	(527	)		$	528			$	1
forwards
Net Investment Hedge
Our primary exposure to be hedged is our net investment in Aflac Japan, which is affected by changes in the yen/dollar exchange rate. To mitigate this exposure, we have designated a majority of the Parent Company's yen-denominated liabilities (Samurai and Uridashi notes and yen-denominated loans - see Note 9) as nonderivative hedges and designated foreign currency forwards and options as derivative hedges of the foreign currency exposure of our net investment in Aflac Japan.
We used foreign exchange forwards and options to economically hedge foreign exchange risk on 52.5 billion yen and 50.0 billion yen of repatriation received from Aflac Japan in July 2014 and December 2014, respectively. As of December 31, 2014, we had entered into foreign exchange forwards as part of an economic hedge on 157.5 billion yen of future profit repatriation.
Our net investment hedge was effective for the years ended December 31, 2014, 2013 and 2012.
Non-qualifying Strategies
For our 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 derivative and other gains (losses). The amount of gain or loss recognized in earnings for our 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 income or perpetual securities associated with these swaps is recorded through other comprehensive income.
We have cross-currency interest rate swap agreements related to our $750 million senior notes due November 2024, $700 million senior notes due June 2023, $400 million senior notes due February 2017, $350 million senior notes due February 2022, and $500 million subordinated debentures due September 2052. Changes in the values of these swaps are recorded through current period earnings. For additional information regarding these swaps, see Note 9.
Impact of Derivatives and Hedging Instruments
The following table summarizes the impact to realized investment gains (losses) and other comprehensive income (loss) from all derivatives and hedging instruments for the years ended December 31.
	2014										2013										2012
(In millions)	Realized Investment					Other					Realized Investment					Other					Realized					Other
	Gains (Losses)					Comprehensive					Gains (Losses)					Comprehensive					Investment					Comprehensive
						Income (Loss)(1)										Income (Loss)(1)					Gains (Losses)					Income (Loss)(1)
Qualifying hedges:
Cash flow hedges:
Foreign currency swaps		$	(2	)			$	(17	)			$	(2	)			$	(10	)			$	(3	)			$	(22	)
Total cash flow hedges		(2		)			(17		)			(2		)			(10		)			(3		)			(22		)
Fair value hedges:
Foreign currency forwards (2)		(16		)			0					(35		)			0					(7		)			0
Foreign currency options (2)		(3		)			0					0					0					0					0
Interest rate swaptions (2)		(2		)			0					17					0					0					0
Total fair value hedges		(21		)			0					(18		)			0					(7		)			0
Net investment hedge:
Non-derivative hedging		0					39					0					155					0					96
instruments
Foreign currency swaps		0					0					0					(104		)			0					0
Foreign currency forwards		0					89					0					24					0					0
Foreign currency options		0					(3		)			0					4					0					0
Total net investment hedge		0					125					0					79					0					96
Non-qualifying strategies:
Foreign currency swaps		151					0					346					0					111					0
Foreign currency forwards		(11		)			0					0					0					0					0
Foreign currency options		0					0					11					0					0					0
Credit default swaps		3					0					31					0					64					0
Interest rate swaps		(1		)			0					(8		)			0					(14		)			0
Interest rate swaptions		1					0					(29		)			0					0					0
Futures		(89		)			0					(5		)			0					0					0
Total non- qualifying strategies		54					0					346					0					161					0
Total		$	31				$	108				$	326				$	69				$	151				$	74
(1) Cash flow hedge items 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 shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail)
There was no gain or loss reclassified from accumulated other comprehensive income (loss) into earnings related to our designated cash flow hedges and net investment hedge for the years ended December 31, 2014, 2013 and 2012. As of December 31, 2014, 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 are immaterial.
Offsetting of Financial Instruments and Derivatives
Certain 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 Company and a counterparty in the event of default or upon the occurrence of certain termination events. Collateral support agreements with certain of the master netting arrangements provide that the Company will receive or pledge financial collateral in the event either minimum thresholds, or in certain cases ratings levels, have been reached.
We have securities lending agreements with unaffiliated financial institutions that post collateral to us in return for the use of our fixed maturity securities (see Note 3). When we have 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 would allow us to keep and apply collateral received if the counterparty failed to return the securities borrowed from us as contractually agreed. For additional information on the Company's accounting policy for securities lending, see
Note 1.
The tables below summarize our derivatives and securities lending transactions as of December 31, and as reflected in the tables, in accordance with GAAP, our policy is to not offset these financial instruments in the Consolidated Balance Sheets.
Offsetting of Financial Assets and Derivative Assets
2014
																			Gross Amounts Not Offset
																			in Balance Sheet
(In millions)	Gross Amount of Recognized Assets						Gross Amount						Net Amount of Assets Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Received						Net Amount
							Offset in
							Balance Sheet
Derivative assets:
Foreign currency swaps		$	746					$	0					$	746					$	0				$	(568	)				$	178
Foreign currency forwards		56						0						56						0					(51		)				5
Total derivative assets,		802						0						802						0					(619		)	(1)			183
subject to a master
netting arrangement
or offsetting
arrangement
Securities lending and		2,149						0						2,149						0					(2,149		)				0
similar arrangements
Total		$	2,951					$	0					$	2,951					$	0				$	(2,768	)				$	183
(1) Consists of $153 of pledged securities and $466 of cash.
2013
																			Gross Amounts Not Offset
																			in Balance Sheet
(In millions)	Gross Amount of Recognized Assets						Gross Amount Offset in Balance Sheet						Net Amount of Assets Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Received						Net Amount
Derivative assets:
Foreign currency swaps		$	445					$	0					$	445					$	0				$	(276	)				$	169
Foreign currency forwards		17						0						17						0					(16		)				1
Foreign currency options		4						0						4						0					(3		)				1
Credit default swaps		1						0						1						0					0						1
Interest rate swaps		1						0						1						0					0						1
Interest rate swaptions		20						0						20						0					0						20
Total derivative assets,		488						0						488						0					(295		)	(1)			193
subject to a master
netting arrangement
or offsetting
arrangement
Securities lending and		5,656						0						5,656						0					(5,656		)				0
similar arrangements
Total		$	6,144					$	0					$	6,144					$	0				$	(5,951	)				$	193
(1) Consists entirely of cash.
Offsetting of Financial Liabilities and Derivative Liabilities
2014
																			Gross Amounts Not Offset
																			in Balance Sheet
(In millions)	Gross Amount of Recognized Liabilities						Gross Amount Offset in Balance Sheet						Net Amount of Liabilities Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Pledged						Net Amount
Derivative liabilities:
Foreign currency swaps		$	(318	)				$	0					$	(318	)				$	0				$	0					$	(318	)
Foreign currency forwards		(1,912		)				0						(1,912		)				0					1,439						(473		)
Foreign currency options		(33		)				0						(33		)				0					24						(9		)
Interest rate swaptions		(160		)				0						(160		)				0					158						(2		)
Total derivative liabilities,		(2,423		)				0						(2,423		)				0					1,621			(1)			(802		)
subject to a master
netting arrangement
or offsetting
arrangement
Securities lending and		(2,193		)				0						(2,193		)				2,149					0						(44		)
similar arrangements
Total		$	(4,616	)				$	0					$	(4,616	)				$	2,149				$	1,621					$	(846	)
(1) Consists entirely of pledged securities.
2013
																			Gross Amounts Not Offset
																			in Balance Sheet
(In millions)	Gross Amount of Recognized Liabilities						Gross Amount Offset in Balance Sheet						Net Amount of Liabilities Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Pledged						Net Amount
Derivative liabilities:
Foreign currency swaps		$	(218	)				$	0					$	(218	)				$	0				$	1					$	(217	)
Foreign currency forwards		(582		)				0						(582		)				0					0						(582		)
Foreign currency options		(1		)				0						(1		)				0					0						(1		)
Credit default swaps		(4		)				0						(4		)				0					0						(4		)
Interest rate swaptions		(32		)				0						(32		)				0					7						(25		)
Total derivative liabilities,		(837		)				0						(837		)				0					8			(1)			(829		)
subject to a master
netting arrangement
or offsetting
arrangement
Securities lending and		(5,820		)				0						(5,820		)				5,656					0						(164		)
similar arrangements
Total		$	(6,657	)				$	0					$	(6,657	)				$	5,656				$	8					$	(993	)
(1) Consists of $7 of pledged securities and $1 of cash.
For additional information on our financial instruments, see the accompanying Notes 1, 3 and 5.

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS
	Fair Value Hierarchy
	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 as of December 31.
		2014
	(In millions)	Quoted Prices in						Significant						Significant						Total
		Active Markets						Observable						Unobservable						Fair
		for Identical						Inputs						Inputs						Value
		Assets						(Level 2)						(Level 3)
		(Level 1)
	Assets:
	Securities available for sale, carried at
	fair value:
	Fixed maturities:
	Government and agencies		$	18,683					$	515					$	0					$	19,198
	Municipalities		0						1,257						0						1,257
	Mortgage- and asset-backed securities		0						379						223						602
	Public utilities		0						7,897						0						7,897
	Sovereign and supranational		0						1,416						0						1,416
	Banks/financial institutions		0						6,572						26						6,598
	Other corporate		0						28,605						0						28,605
	Total fixed maturities		18,683						46,641						249						65,573
	Perpetual securities:
	Banks/financial institutions		0						2,289						149						2,438
	Other corporate		0						231						0						231
	Total perpetual securities		0						2,520						149						2,669
	Equity securities		19						6						3						28
	Other assets:
	Foreign currency swaps		0						640						106						746
	Foreign currency forwards		0						56						0						56
	Total other assets		0						696						106						802
	Other investments		171						0						0						171
	Cash and cash equivalents		4,658						0						0						4,658
	Total assets		$	23,531					$	49,863					$	507					$	73,901
	Liabilities:
	Foreign currency swaps		$	0					$	0					$	318					$	318
	Foreign currency forwards		0						1,912						0						1,912
	Foreign currency options		0						33						0						33
	Interest rate swaptions		0						160						0						160
	Total liabilities		$	0					$	2,105					$	318					$	2,423
		2013
	(In millions)	Quoted Prices in						Significant						Significant						Total
		Active Markets						Observable						Unobservable						Fair
		for Identical						Inputs						Inputs						Value
		Assets						(Level 2)						(Level 3)
		(Level 1)
	Assets:
	Securities available for sale, carried at
	fair value:
	Fixed maturities:
	Government and agencies		$	14,928					$	504					$	0					$	15,432
	Municipalities		0						1,051						0						1,051
	Mortgage- and asset-backed securities		0						402						369						771
	Public utilities		0						7,562						0						7,562
	Sovereign and supranational		0						1,523						0						1,523
	Banks/financial institutions		0						6,486						23						6,509
	Other corporate		0						25,222						0						25,222
	Total fixed maturities		14,928						42,750						392						58,070
	Perpetual securities:
	Banks/financial institutions		0						2,686						52						2,738
	Other corporate		0						209						0						209
	Total perpetual securities		0						2,895						52						2,947
	Equity securities		14						4						3						21
	Other assets:
Foreign currency swaps		0						341						104						445
Foreign currency forwards		0						17						0						17
Foreign currency options		0						4						0						4
Credit default swaps		0						0						1						1
Interest rate swaps		0						0						1						1
Interest rate swaptions		0						20						0						20
Total other assets		0						382						106						488
Other investments		463						0						0						463
Cash and cash equivalents		2,543						0						0						2,543
Total assets		$	17,948					$	46,031					$	553					$	64,532
Liabilities:
Foreign currency swaps		$	0					$	15					$	203					$	218
Foreign currency forwards		0						582						0						582
Foreign currency options		0						1						0						1
Credit default swaps		0						0						4						4
Interest rate swaptions		0						32						0						32
Total liabilities		$	0					$	630					$	207					$	837
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 as of December 31.
	2014
(In millions)	Carrying					Quoted Prices in						Significant						Significant					Total
	Value					Active Markets						Observable						Unobservable					Fair
						for Identical						Inputs						Inputs					Value
						Assets						(Level 2)						(Level 3)
						(Level 1)
Assets:
Securities held to maturity,
carried at amortized cost:
Fixed maturities:
Government and agencies		$	20,023				$	23,218					$	0					$	0					$	23,218
Municipalities		346					0						417						0						417
Mortgage and asset-backed		43					0						15						31						46
securities
Public utilities		3,342					0						3,603						0						3,603
Sovereign and		2,556					0						2,814						0						2,814
supranational
Banks/financial institutions		4,932					0						5,085						0						5,085
Other corporate		3,000					0						3,314						0						3,314
Total assets		$	34,242				$	23,218					$	15,248					$	31					$	38,497
Liabilities:
Other policyholders’ funds		$	6,031				$	0					$	0					$	5,905					$	5,905
Notes payable		5,268					0						0						5,835						5,835
(excluding capital leases)
Total liabilities		$	11,299				$	0					$	0					$	11,740					$	11,740
						2013
(In millions)	Carrying					Quoted Prices in						Significant						Significant						Total
	Value					Active Markets						Observable						Unobservable						Fair
						for Identical						Inputs						Inputs						Value
						Assets						(Level 2)						(Level 3)
						(Level 1)
Assets:
Securities held to maturity,
carried at amortized cost:
Fixed maturities:
Government and agencies		$	27,362				$	28,708					$	0					$	0					$	28,708
Municipalities		399					0						440						0						440
Mortgage and asset-backed		58					0						20						41						61
securities
Public utilities		3,900					0						3,928						0						3,928
Sovereign and		2,941					0						3,040						0						3,040
supranational
Banks/financial institutions		6,310					0						6,128						0						6,128
Other corporate		3,445					0						3,541						0						3,541
Total assets		$	44,415				$	28,708					$	17,097					$	41					$	45,846
Liabilities:
Other policyholders’ funds		$	5,861				$	0					$	0					$	5,715					$	5,715
Notes payable		4,891					0						0						5,241						5,241
(excluding capital leases)
Total liabilities		$	10,752				$	0					$	0					$	10,956					$	10,956
Fair Value of Financial Instruments
U.S. GAAP requires disclosure of the fair value of certain financial instruments including those that are not carried at fair value. The carrying amounts for cash and cash equivalents, other investments, receivables, accrued investment income, accounts payable, cash collateral and payables for security transactions approximated their fair values due to the short-term nature of these instruments. Liabilities for future policy benefits and unpaid policy claims are not financial instruments as defined by GAAP.
Fixed maturities, perpetual securities, and equity securities
We determine the fair values of our fixed maturity securities, perpetual securities, 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 we obtain 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 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; or 4) bond indices that are comparative in rating, industry, maturity and region.
The pricing data and market quotes we obtain from outside sources, including third party pricing services, are reviewed internally for reasonableness. If a fair value appears unreasonable, we will re-examine the inputs and assess the reasonableness of the pricing data with the vendor. Additionally, we may compare the inputs to relevant market indices and other performance measurements. The output of this analysis is presented to the Company's Valuation and Classifications Subcommittee, or VCS. Based on the analysis provided to the VCS, 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. We have performed verification of the inputs and calculations in any valuation models to confirm that the valuations represent reasonable estimates of fair value.
The fixed maturities classified as Level 3 consist of securities for which there are limited or no observable valuation inputs. For Level 3 securities that are investment grade, we estimate the fair value of these securities by obtaining non-binding broker quotes from a limited number of brokers. These brokers base their quotes on a combination of their knowledge of the current pricing environment and market conditions. We consider these inputs to be unobservable. For Level 3 investments that are below-investment-grade securities, we consider a variety of significant valuation inputs in the valuation process, including forward exchange rates, yen swap rates, dollar swap rates, interest rate volatilities, credit spread data on specific issuers, assumed default and default recovery rates, and certain probability assumptions. In obtaining these valuation inputs, we have determined that certain pricing assumptions and data used by our pricing sources are difficult to validate or corroborate by the market and/or appear to be internally developed rather than observed in or corroborated by the market. The use of these unobservable valuation inputs causes more subjectivity in the valuation process for these securities.
Historically, we have not adjusted the quotes or prices we obtain from the pricing services and brokers we use.
The following tables present the pricing sources for the fair values of our fixed maturities, perpetual securities, and equity securities as of December 31.
		2014
(In millions)		Quoted Prices in Active Markets for Identical Assets						Significant Observable Inputs						Significant Unobservable Inputs						Total
		(Level 1)						(Level 2)						(Level 3)						Fair
																				Value
Securities available for sale, carried at fair value:
Fixed maturities:
Government and agencies:
Third party pricing vendor			$	18,683					$	515					$	0					$	19,198
Total government and agencies			18,683						515						0						19,198
Municipalities:
Third party pricing vendor			0						1,257						0						1,257
Total municipalities			0						1,257						0						1,257
Mortgage- and asset-backed securities:
Third party pricing vendor			0						379						0						379
Broker/other			0						0						223						223
Total mortgage- and asset-backed securities			0						379						223						602
Public utilities:
Third party pricing vendor			0						7,897						0						7,897
Total public utilities			0						7,897						0						7,897
Sovereign and supranational:
Third party pricing vendor			0						1,416						0						1,416
Total sovereign and supranational			0						1,416						0						1,416
Banks/financial institutions:
Third party pricing vendor			0						6,514						0						6,514
Broker/other			0						58						26						84
Total banks/financial institutions			0						6,572						26						6,598
Other corporate:
Third party pricing vendor			0						28,605						0						28,605
Total other corporate			0						28,605						0						28,605
Total fixed maturities			18,683						46,641						249						65,573
Perpetual securities:
Banks/financial institutions:
Third party pricing vendor			0						2,289						0						2,289
Broker/other			0						0						149						149
Total banks/financial institutions			0						2,289						149						2,438
Other corporate:
Third party pricing vendor			0						231						0						231
Total other corporate			0						231						0						231
Total perpetual securities			0						2,520						149						2,669
Equity securities:
Third party pricing vendor			19						6						0						25
Broker/other			0						0						3						3
Total equity securities			19						6						3						28
Total securities available for sale			$	18,702					$	49,167					$	401					$	68,270
		2014
(In millions)		Quoted Prices in Active Markets for Identical Assets						Significant Observable Inputs						Significant Unobservable Inputs						Total
		(Level 1)						(Level 2)						(Level 3)						Fair
																				Value
Securities held to maturity, carried at amortized cost:
Fixed maturities:
Government and agencies:
Third party pricing vendor			$	23,218					$	0					$	0					$	23,218
Total government and agencies			23,218						0						0						23,218
Municipalities:
Third party pricing vendor			0						417						0						417
Total municipalities			0						417						0						417
Mortgage- and asset-backed securities:
Third party pricing vendor			0						15						0						15
Broker/other			0						0						31						31
Total mortgage- and asset-backed securities			0						15						31						46
Public utilities:
Third party pricing vendor			0						3,603						0						3,603
Total public utilities			0						3,603						0						3,603
Sovereign and supranational:
Third party pricing vendor			0						2,814						0						2,814
Total sovereign and supranational			0						2,814						0						2,814
Banks/financial institutions:
Third party pricing vendor			0						5,085						0						5,085
Total banks/financial institutions			0						5,085						0						5,085
Other corporate:
Third party pricing vendor			0						3,287						0						3,287
Broker/other			0						27						0						27
Total other corporate			0						3,314						0						3,314
Total securities held to maturity			$	23,218					$	15,248					$	31					$	38,497
		2013
(In millions)		Quoted Prices in Active Markets						Significant Observable						Significant Unobservable Inputs						Total
		for Identical Assets						Inputs						(Level 3)						Fair
		(Level 1)						(Level 2)												Value
Securities available for sale, carried at fair value:
Fixed maturities:
Government and agencies:
Third party pricing vendor			$	14,928					$	504					$	0					$	15,432
Total government and agencies			14,928						504						0						15,432
Municipalities:
Third party pricing vendor			0						1,051						0						1,051
Total municipalities			0						1,051						0						1,051
Mortgage- and asset-backed securities:
Third party pricing vendor			0						402						0						402
Broker/other			0						0						369						369
Total mortgage- and asset-backed securities			0						402						369						771
Public utilities:
Third party pricing vendor			0						7,562						0						7,562
Total public utilities			0						7,562						0						7,562
Sovereign and supranational:
Third party pricing vendor			0						1,523						0						1,523
Total sovereign and supranational			0						1,523						0						1,523
Banks/financial institutions:
Third party pricing vendor			0						6,486						0						6,486
Broker/other			0						0						23						23
Total banks/financial institutions			0						6,486						23						6,509
Other corporate:
Third party pricing vendor			0						25,220						0						25,220
Broker/other			0						2						0						2
Total other corporate			0						25,222						0						25,222
Total fixed maturities			14,928						42,750						392						58,070
Perpetual securities:
Banks/financial institutions:
Third party pricing vendor			0						2,686						52						2,738
Total banks/financial institutions			0						2,686						52						2,738
Other corporate:
Third party pricing vendor			0						209						0						209
Total other corporate			0						209						0						209
Total perpetual securities			0						2,895						52						2,947
Equity securities:
Third party pricing vendor			14						4						0						18
Broker/other			0						0						3						3
Total equity securities			14						4						3						21
Total securities available for sale			$	14,942					$	45,649					$	447					$	61,038
		2013
(In millions)		Quoted Prices in Active Markets						Significant Observable						Significant Unobservable Inputs						Total
		for Identical Assets						Inputs						(Level 3)						Fair
		(Level 1)						(Level 2)												Value
Securities held to maturity, carried at amortized cost:
Fixed maturities:
Government and agencies:
Third party pricing vendor			$	28,708					$	0					$	0					$	28,708
Total government and agencies			28,708						0						0						28,708
Municipalities:
Third party pricing vendor			0						440						0						440
Total municipalities			0						440						0						440
Mortgage- and asset-backed securities:
Third party pricing vendor			0						20						0						20
Broker/other			0						0						41						41
Total mortgage- and asset-backed securities			0						20						41						61
Public utilities:
Third party pricing vendor			0						3,928						0						3,928
Total public utilities			0						3,928						0						3,928
Sovereign and supranational:
Third party pricing vendor			0						3,040						0						3,040
Total sovereign and supranational			0						3,040						0						3,040
Banks/financial institutions:
Third party pricing vendor			0						6,128						0						6,128
Total banks/financial institutions			0						6,128						0						6,128
Other corporate:
Third party pricing vendor			0						3,509						0						3,509
Broker/other			0						32						0						32
Total other corporate			0						3,541						0						3,541
Total securities held to maturity			$	28,708					$	17,097					$	41					$	45,846
The following is a discussion of the determination of fair value of our remaining financial instruments.
Derivatives
We use 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 fair values of the foreign currency forwards, options, and interest rate swaptions associated with certain fixed-maturity securities; the foreign currency forwards and options used to hedge certain portions of forecasted yen cash flows; the foreign currency swaps associated with certain senior notes and our subordinated debentures; and the interest rate swap associated with our yen-denominated notes are based on the amounts we would expect to receive or pay. The determination of the fair value of these derivatives is based on observable market inputs, therefore they are classified as Level 2.
For derivatives associated with VIEs where we are the primary beneficiary, we are 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. We receive valuations from a third party pricing vendor for these derivatives. Based on an analysis of these derivatives and a review of the methodology employed by the pricing vendor, we 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 our consolidated VIEs are classified as Level 3 of the fair value hierarchy.
Other policyholders' funds
The largest component of the other policyholders' funds liability is our annuity line of business in Aflac Japan. Our annuities have fixed benefits and premiums. For this product, we estimated 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. We periodically check the cash value against discounted cash flow projections for reasonableness. We consider our inputs for this valuation to be unobservable and have accordingly classified this valuation as Level 3.
Notes payable
The fair values of our publicly issued notes payable classified as Level 3 were obtained from a limited number of independent brokers. These brokers base their quotes on a combination of their knowledge of the current pricing environment and market conditions. We consider these inputs to be unobservable. The fair values of our yen-denominated loans approximate their carrying values.
Level 3 Rollforward and Transfers between Hierarchy Levels
The following tables present the changes in fair value of our available-for-sale investments and derivatives classified as Level 3 as of December 31.
2014
	Fixed Maturities																				Perpetual				Equity			Derivatives(1)
																					Securities				Securities
(In millions)	Mortgage-				Public				Sovereign				Banks/				Other				Banks/							Interest			Foreign			Credit			Total
	and				Utilities				and				Financial				Corporate				Financial							Rate			Currency			Default
	Asset-								Supranational				Institutions								Institutions							Swaps			Swaps			Swaps
	Backed
	Securities
Balance, beginning of period	$	369			$	0			$	0			$	23			$	0			$	52			$	3		$	1		$	(99	)	$	(3	)	$	346
Realized investment gains (losses) included	0				0				0				0				0				0				0			(1		)	(191		)	3			(189		)
in earnings
Unrealized gains (losses) included in other	(134		)		0				0				3				0				8				0			0			(17		)	0			(140		)
comprehensive income (loss)
Purchases, issuances, sales and settlements:
Purchases	0				0				0				0				0				0				0			0			0			0			0
Issuances	0				0				0				0				0				0				0			0			0			0			0
Sales	0				0				0				0				0				(60		)		0			0			0			0			(60		)
Settlements	(12		)		0				0				0				0				0				0			0			95			0			83
Transfers into Level 3(2)	0				0				0				0				0				149				0			0			0			0			149
Transfers out of Level 3	0				0				0				0				0				0				0			0			0			0			0
Balance, end of period	$	223			$	0			$	0			$	26			$	0			$	149			$	3		$	0		$	(212	)	$	0		$	189
Changes in unrealized gains (losses) relating	$	0			$	0			$	0			$	0			$	0			$	0			$	0		$	(1	)	$	(191	)	$	3		$	(189	)
to Level 3 assets and liabilities still held at
the end of the period included in realized
investment gains (losses)
(1) Derivative assets and liabilities are presented net
(2) Due to use of estimated redemption price
2013
	Fixed Maturities																				Perpetual				Equity			Derivatives(1)
																					Securities				Securities
(In millions)	Mortgage-				Public				Sovereign				Banks/				Other				Banks/							Interest			Foreign			Credit			Total
	and				Utilities				and				Financial				Corporate				Financial							Rate			Currency			Default
	Asset-								Supranational				Institutions								Institutions							Swaps			Swaps			Swaps
	Backed
	Securities
Balance, beginning of period	$	338			$	420			$	418			$	1,024			$	986			$	215			$	4		$	29		$	(172	)	$	(65	)	$	3,197
Realized investment gains (losses) included	0				0				0				0				0				0				0			(8		)	84			29			105
in earnings
Unrealized gains (losses) included in other	(72		)		(20		)		0				(4		)		0				3				(1		)	0			(11		)	0			(105		)
comprehensive income (loss)
Purchases, issuances, sales and settlements:
Purchases	0				0				0				0				0				0				0			0			0			0			0
Issuances	0				0				0				0				0				0				0			0			0			0			0
Sales	0				(400		)		0				0				0				0				0			(20		)	0			33			(387		)
Settlements	(13		)		0				0				0				0				0				0			0			0			0			(13		)
Transfers into Level 3(2)	125				0				0				0				0				49				0			0			0			0			174
Transfers out of Level 3(3)	(9		)		0				(418		)		(997		)		(986		)		(215		)		0			0			0			0			(2,625		)
Balance, end of period	$	369			$	0			$	0			$	23			$	0			$	52			$	3		$	1		$	(99	)	$	(3	)	$	346
Changes in unrealized gains (losses) relating	$	0			$	0			$	0			$	0			$	0			$	0			$	0		$	(8	)	$	84		$	29		$	105
to Level 3 assets and liabilities still held at
the end of the period included in realized
investment gains (losses)
(1) Derivative assets and liabilities are presented net
(2) Due to a lack of visibility to observe significant inputs to price
(3) A result of changing our pricing methodology to a valuation method that uses observable market data as significant inputs to estimate fair value
Transfers into and/or out of Level 3 are attributable to a change in the observability of inputs. The most significant transfer out of Level 3 into Level 2 during 2013 related to our callable reverse dual-currency bonds (RDCs). RDCs are securities that have principal denominated in yen while paying U.S. dollar (USD) coupons. The market standard approach is to use implied volatility to value options or instruments with optionality because historical volatility may not represent current market participants' expectations about future volatility. Under our previous valuation approach, we used historical foreign exchange volatility as an input for valuing these investments. Given the importance of this input to the overall valuation of these RDCs and the determination of this input to be unobservable, we made the decision at December 31, 2011 to move these holdings to Level 3 of the fair value hierarchy. During the first quarter of 2013, we implemented a new valuation methodology for these securities that relies on comparable securities in the market, the observable forward foreign exchange curve and other market inputs. Given that the significant inputs to the valuation of these items are now based on observable data, in the first quarter of 2013, we transferred these bonds from Level 3 to Level 2 of the fair value hierarchy.
In addition to the callable RDCs, we transferred certain other corporate securities from Level 3 to Level 2 in the first quarter of 2013. Prices for these securities were previously obtained from brokers and/or arrangers with minimal transparency around how the valuation was determined. Similar to the RDCs, these securities are now valued using the same methodology described above for our other privately issued securities.
There were no transfers between Level 1 and 2 for the years ended December 31, 2014 and 2013.
Level 3 Significant Unobservable Input Sensitivity
The following tables summarize the significant unobservable inputs used in the valuation of our Level 3 available-for-sale investments and derivatives as of December 31. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments.
2014
(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
												(Weighted Average)
Assets:
Securities available for sale, carried at fair value:
Fixed maturities:
Mortgage- and asset-backed securities			$	223				Consensus pricing		Offered quotes		N/A	(d)
Banks/financial institutions			26					Consensus pricing		Offered quotes		N/A	(d)
Perpetual securities:
Banks/financial institutions			149					Consensus pricing		Offered quotes		N/A	(d)
Equity securities			3					Net asset value		Offered quotes		$1 - $677 ($6)
Other assets:
Foreign currency swaps			8					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
										Interest rates (JPY)		.53% - 1.34%	(b)
										CDS spreads		16 - 105 bps
										Foreign exchange rates		20.50%	(c)
			98					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
										Interest rates (JPY)		.53% - 1.34%	(b)
										Foreign exchange rates		20.50%	(c)
Total assets			$	507
(a) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
(b) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
(c) Based on 10 year volatility of JPY/USD exchange rate
(d) N/A represents securities where we receive unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
2014
(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
												(Weighted Average)
Liabilities:
Foreign currency swaps			$	176				Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
										Interest rates (JPY)		.53% - 1.34%	(b)
										CDS spreads		16 - 105 bps
										Foreign exchange rates		20.50%	(c)
			111					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
										Interest rates (JPY)		.53% - 1.34%	(b)
										CDS spreads		13 - 145 bps
			31					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
										Interest rates (JPY)		.53% - 1.34%	(b)
										Foreign exchange rates		20.50%	(c)
Total liabilities			$	318
(a) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
(b) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
(c) Based on 10 year volatility of JPY/USD exchange rate
2013
(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
												(Weighted Average)
Assets:
Securities available for sale, carried at fair value:
Fixed maturities:
Mortgage- and asset-backed securities			$	369				Consensus pricing		Offered quotes		N/A	(e)
Banks/financial institutions			23					Consensus pricing		Offered quotes		N/A	(e)
Perpetual securities:
Banks/financial institutions			52					Consensus pricing		Offered quotes		N/A	(e)
Equity securities			3					Net asset value		Offered quotes		$1-$774 ($7)
Other assets:
Foreign currency swaps			30					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										CDS spreads		16 - 141 bps
										Foreign exchange rates		21.16%	(d)
			9					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										CDS spreads		17 - 149 bps
			65					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										Foreign exchange rates		21.16%	(d)
Credit default swaps			1					Discounted cash flow		Base correlation		65% - 76% (72%)	(a)
										CDS spreads		65 - 106 (92) bps
										Recovery rate		37.00%
Interest rate swaps			1					Discounted cash flow		Base correlation		65% - 76% (72%)	(a)
										CDS spreads		65 - 106 (92) bps
										Recovery rate		37.00%
Total assets			$	553
(a) Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
(d) Based on 10 year volatility of JPY/USD exchange rate
(e) N/A represents securities where we receive unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
2013
(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
												(Weighted Average)
Liabilities:
Foreign currency swaps			$	99				Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										CDS spreads		16 - 141 bps
										Foreign exchange rates		21.16%	(d)
			24					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										CDS spreads		11 - 189 bps
			80					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
										Interest rates (JPY)		.93% - 2.02%	(c)
										Foreign exchange rates		21.16%	(d)
Credit default swaps			4					Discounted cash flow		Base correlations		65% - 76% (72%)	(a)
										CDS spreads		65 - 106 (92) bps
										Recovery rate		37.00%
Total liabilities			$	207
(a) Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
(d) Based on 10 year volatility of JPY/USD exchange rate
The following is a discussion of the significant unobservable inputs or valuation technique used in determining the fair value of securities and derivatives classified as Level 3.
Net Asset Value
We hold 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 our valuation model price is overridden because it implies a value that is not consistent with current market conditions, we will solicit bids from a limited number of brokers. We also receive unadjusted prices from brokers for our 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, CDS Spreads, Foreign Exchange Rates
The significant drivers of the valuation of the interest and foreign exchange swaps are interest rates, foreign exchange rates and CDS spreads. Our swaps have long maturities that increase the sensitivity of the swaps to interest rate fluctuations. Since most of our yen-denominated cross currency swaps are in a net liability position, an increase in interest rates will decrease the liabilities and increase the value of the swap.
Foreign exchange swaps also have a lump-sum final settlement of foreign exchange principal receivables at the termination of the swap. An increase in yen interest rates will decrease the value of the final settlement foreign exchange receivables and decrease the value of the swap, and an increase in USD interest rates increase the swap value.
A similar sensitivity pattern is observed for the foreign exchange rates. When the spot U.S. dollar/Japanese yen (USD/JPY) foreign exchange rate decreases and the swap is receiving a final exchange payment in JPY, the swap value will increase due to the appreciation of the JPY. Most of our swaps are designed to receive payments in JPY at the termination and will thus be impacted by the USD/JPY foreign exchange rate in this way. In cases where there is no final foreign exchange receivable in JPY and we are paying JPY as interest payments and receiving USD, a decrease in the foreign exchange rate will lead to a decrease in the swap value.
The extinguisher feature in most of our 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, we apply 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.
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.
Interest rates, CDS spreads, and foreign exchange rates are unobservable inputs in the determination of fair value of foreign currency swaps.
Base Correlations, CDS Spreads, Recovery Rates
Our CDOs are tranches on baskets of single-name credit default swaps. The risks in these types of synthetic CDOs come from the single-name CDS risk and the correlations between the single names. The valuation of synthetic CDOs is dependent on the calibration of market prices for interest rates, single name CDS default probabilities and base correlation using financial modeling tools. Since there is limited or no observable data available for these tranches, these base correlations must be obtained from commonly traded market tranches such as the CDX and iTraxx indices. From the historical prices of these indices, base correlations can be obtained to develop a pricing curve of CDOs with different seniorities. Since the reference entities of the market indices do not match those in our portfolio underlying the synthetic CDO to be valued, several processing steps are taken to map the securities in our portfolio to the indices. With the base correlation determined and the appropriate spreads selected, a valuation is calculated. An increase in the CDS spreads in the underlying portfolio leads to a decrease in the value due to higher probability of defaults and losses. The impact on the valuation due to base correlation depends on a number of factors, including the riskiness between market tranches and the modeled tranche based on our portfolio and the equivalence between detachment points in these tranches. Generally speaking, an increase in base correlation will decrease the value of the senior tranches while increasing the value of junior tranches. This may result in a positive or negative value change.
The CDO tranches in our portfolio are junior tranches and, due to the low level of credit support for these tranches, exhibit equity-like behavior. As a result, an increase in recovery rates tends to cause their values to decrease.
Our interest rate swaps are linked to the underlying synthetic CDOs. The valuation of these swaps is performed using a similar approach to that of the synthetic CDOs themselves; that is, the base correlation model is used to ensure consistency between the synthetic CDOs and the swaps.
Base correlations, CDS spreads, and recovery rates are unobservable inputs in the determination of fair value of credit default swaps and interest rate swaps.
For additional information on our investments and financial instruments, see the accompanying Notes 1, 3 and 4.

DEFERRED_POLICY_ACQUISITION_CO

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES	12 Months Ended
	Dec. 31, 2014
Deferred Policy Acquisition Costs and Insurance Expense Disclosure [Abstract]
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES	DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES
	Consolidated policy acquisition costs deferred were $1.3 billion in 2014, compared with $1.4 billion in 2013 and $1.7 billion in 2012. The following table presents a rollforward of deferred policy acquisition costs by segment for the years ended December 31.
		2014								2013
	(In millions)	Japan				U.S.				Japan				U.S.
	Deferred policy acquisition costs:
	Balance, beginning of year		$	5,819			$	2,979			$	6,801			$	2,857
	Capitalization		790				548				893				555
	Amortization		(649		)		(459		)		(641		)		(433		)
	Foreign currency translation and other		(749		)		(6		)		(1,234		)		0
	Balance, end of year		$	5,211			$	3,062			$	5,819			$	2,979
	Commissions deferred as a percentage of total acquisition costs deferred were 77% in 2014, compared with 81% in 2013 and 84% in 2012.
	Personnel, compensation and benefit expenses as a percentage of insurance expenses were 52% in 2014, compared with 51% in 2013 and 2012. Advertising expense, which is included in insurance expenses in the consolidated statements of earnings, was as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Advertising expense:
	Aflac Japan		$	103			$	112			$	127
	Aflac U.S.		126				128				127
	Total advertising expense		$	229			$	240			$	254
	Depreciation and other amortization expenses, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Depreciation expense		$	47			$	56			$	60
	Other amortization expense		8				13				7
	Total depreciation and other amortization expense		$	55			$	69			$	67
	Lease and rental expense, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Lease and rental expense:
	Aflac Japan		$	52			$	55			$	71
	Aflac U.S.		15				10				9
	Other		1				1				1
	Total lease and rental expense		$	68			$	66			$	81
	Advertising, lease and rental expense decreased for Aflac Japan in 2014 and 2013 compared with 2012 due to the weakening of the yen relative to the U.S. dollar.

POLICY_LIABILITIES

POLICY LIABILITIES	12 Months Ended
	Dec. 31, 2014
Policy liabilities [Abstract]
POLICY LIABILITIES	POLICY LIABILITIES
	Policy liabilities consist of future policy benefits, unpaid policy claims, unearned premiums, and other policyholders' funds, which accounted for 78%, 4%, 11% and 7% of total policy liabilities at December 31, 2014, respectively. We regularly review the adequacy of our policy liabilities in total and by component.
	The liability for future policy benefits as of December 31 consisted of the following:
				Liability Amounts						Interest Rates
	(In millions)	Policy		2014		2013				Year of			In 20
		Issue Year								Issue			Years
	Health insurance:
	Japan:	2002 - 2014		$	3,900	$	3,370			1.25 - 2.5	%		1.25 - 2.5	%
		1974 - 2013		3,449		3,889				2.7 - 2.75			2.25 - 2.75
		1998 - 2014		10,641		11,763				3			3
		1997 - 1999		2,461		2,842				3.5			3.5
		1994 - 1996		3,023		3,483				4.0 - 4.5			4.0 - 4.5
		1987 - 1994		14,394		16,727				5.5			5.5
		1985 - 1991		1,923		2,262				5.25 - 6.75			5.25 - 5.5
		1978 - 1984		2,260		2,699				6.5			5.5
	U.S.:	2012 - 2014		588		345				3.0 - 3.75			3.0 - 3.75
		2011		276		243				4.75			4.75
		2005 - 2010		2,951		2,897				5.5			5.5
		1988 - 2004		706		725				8			6
		1986 - 2004		1,293		1,301				6			6
		1981 - 1986		183		190				6.5 - 7.0			5.5 - 6.5
		1998 - 2004		1,260		1,237				7			7
		Other		21		22
	Life insurance:
	Japan:	2013 - 2014		312		59				1.5 - 1.75			1.5 - 1.75
		2001 - 2013		3,674		3,009				1.65 - 1.85			1.65 - 1.85
		2011 - 2014		2,298		1,584				2			2
		2009 - 2011		1,890		1,648				2.25			2.25
		2005 - 2011		1,214		1,211				2.5			2.5
		1985 - 2006		2,006		2,303				2.7			2.25
		2007 - 2011		1,010		1,025				2.75			2.75
		1999 - 2011		1,944		2,164				3			3
		1996 - 2009		633		721				3.5			3.5
		1994 - 1996		884		1,021				4.0 - 4.5			4.0 - 4.5
	U.S.:	1956 - 2014		452		396				3.5 - 6.0			3.5 - 6.0
	Total			$	65,646	$	69,136
	The weighted-average interest rates reflected in the consolidated statements of earnings for future policy benefits for Japanese policies were 3.8% in 2014, compared with 3.9% in 2013 and 4.0% in 2012; and for U.S. policies, 5.7% in 2014, compared with 5.8% in 2013 and 6.0% in 2012.
	Changes in the liability for unpaid policy claims were as follows for the years ended December 31:
	(In millions)	2014				2013					2012
	Unpaid supplemental health claims, beginning of year		$	3,537			$	3,781				$	3,749
	Less reinsurance recoverables		9				10					0
	Net balance, beginning of year		3,528				3,771					3,749
	Add claims incurred during the year related to:
	Current year		6,866				7,215					8,013
	Prior years		(301		)		(236		)			(173		)
	Total incurred		6,565				6,979					7,840
	Less claims paid during the year on claims incurred during:
	Current year		4,532				4,834					5,453
	Prior years		1,873				1,931					2,082
	Total paid		6,405				6,765					7,535
	Effect of foreign exchange rate changes on unpaid claims		(283		)		(457		)			(283		)
	Net balance, end of year		3,405				3,528					3,771
	Add reinsurance recoverables		7				9					10
	Unpaid supplemental health claims, end of year		3,412				3,537					3,781
	Unpaid life claims, end of year		218				226					253
	Total liability for unpaid policy claims		$	3,630			$	3,763				$	4,034
	The incurred claims development related to prior years reflects favorable development in the unpaid policy claims liability. This favorable development is primarily in our lines of business in Japan.
	As of December 31, 2014 and 2013, unearned premiums consisted primarily of discounted advance premiums on deposit. Discounted advance premiums are premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as premium revenue over the contractual premium payment period. These advanced premiums represented 80% of the December 31, 2014 and 82% of the December 31, 2013 unearned premiums balances.
	As of December 31, 2014 and 2013, the largest component of the other policyholders' funds liability is our annuity line of business in Aflac Japan. Our annuities have fixed benefits and premiums. These annuities represented 98% of the December 31, 2014 and 93% of the December 31, 2013 other policyholders' funds liability.

REINSURANCE

REINSURANCE	12 Months Ended
	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
REINSURANCE	REINSURANCE
	Effective October 1, 2014 and September 30, 2013, we entered into coinsurance reinsurance transactions whereby we ceded 16.7% and 33.3%, respectively, of the hospital benefit of one of Aflac Japan’s closed medical in-force blocks of business. We recorded the gain related to these transactions as a deferred profit liability on business sold through reinsurance on our consolidated balance sheets. The deferred profit liability of $820 million, as of December 31, 2014, included in future policy benefits in the consolidated balance sheet, is being amortized into income over the expected lives of the policies. The corresponding reinsurance recoverable is included in other assets in the consolidated balance sheet and totaled $838 million as of December 31, 2014.
	Effective December 31, 2014, we entered into a retrocession coinsurance reinsurance transaction whereby we assumed 8.35% of the reinsured hospital benefit of one of Aflac Japan’s closed medical in-force blocks of business through our subsidiary CAIC. The agreement had no impact on the consolidated balance sheet and statement of operations as of December 31, 2014.
	The following table reconciles direct premium income and direct benefits and claims to net amounts after the effect of reinsurance for the years ended December 31.
	(In millions)	2014				2013
	Direct premium income		$	19,412			$	20,233
	Ceded to other companies:
	Ceded Aflac Japan closed medical block		(311		)		(76		)
	Other		(39		)		(34		)
	Assumed from other companies		10				12
	Net premium income		$	19,072			$	20,135
	Direct benefits and claims		$	13,235			$	13,903
	Ceded benefits and change in reserves for future benefits:
	Ceded Aflac Japan closed medical block		(276		)		(67		)
	Other		(27		)		(31		)
	Assumed from other companies		5				8
	Benefits and claims, net		$	12,937			$	13,813
	Reinsurance does not relieve us from our obligations to policyholders. In the event that the reinsurer is unable to meet their obligations, we remain liable for the reinsured claims.

NOTES_PAYABLE

NOTES PAYABLE	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
NOTES PAYABLE	NOTES PAYABLE
	A summary of notes payable as of December 31 follows:
	(In millions)	2014				2013
	3.45% senior notes due August 2015		$	300			$	300
	2.65% senior notes due February 2017		653		(1)		655		(1)
	8.50% senior notes due May 2019		850				850
	4.00% senior notes due February 2022		350		(2)		349		(2)
	3.625% senior notes due June 2023		700				700
	3.625% senior notes due November 2024		749		(2)		0
	6.90% senior notes due December 2039		397		(2)		396		(2)
	6.45% senior notes due August 2040		448		(2)		448		(2)
	5.50% subordinated debentures due September 2052		500				500
	Yen-denominated Uridashi notes:
	2.26% notes due September 2016 (principal amount 8 billion yen)		66				76
	Yen-denominated Samurai notes:
	1.47% notes paid July 2014 (principal amount 28.7 billion yen)		0				272
	1.84% notes due July 2016 (principal amount 15.8 billion yen)		131				150
	Variable interest rate notes paid July 2014 (1.30% in 2013, principal amount		0				52
	5.5 billion yen)
	Yen-denominated loans:
	3.60% loan due July 2015 (principal amount 10 billion yen)		83				95
	3.00% loan due August 2015 (principal amount 5 billion yen)		41				48
	Capitalized lease obligations payable through 2019		14				6
	Total notes payable		$	5,282			$	4,897
	(1) Principal amount plus an issuance premium that is being amortized over the life of the notes
	(2) Principal amount net of an issuance discount that is being amortized over the life of the notes
	In November 2014, the Parent Company issued $750 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.625% per annum, payable semi-annually, and have a ten-year maturity. These notes are redeemable at our 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 treasury rate plus 20 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. We entered into cross-currency interest rate swaps to reduce interest expense by converting the dollar-denominated principal and interest on the senior notes we issued into yen-denominated obligations. By entering into the swaps, we economically converted our $750 million liability into an 85.3 billion yen liability and reduced the interest rate on this debt from 3.625% in dollars to 1.00% in yen.
	In June 2013, the Parent Company issued $700 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.625% per annum, payable semi-annually, and have a ten-year maturity. These notes are redeemable at our 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 treasury rate plus 20 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. We entered into cross-currency interest rate swaps to reduce interest expense by converting the dollar-denominated principal and interest on the senior notes we issued into yen-denominated obligations. By entering into these swaps, we economically converted our $700 million liability into a 69.8 billion yen liability and reduced the interest rate on this debt from 3.625% in dollars to 1.50% in yen.
	In September 2012, the Parent Company issued $450 million of subordinated debentures through a U.S. public debt offering. The debentures bear interest at a fixed rate of 5.50% per annum, payable quarterly, and have a 40-year maturity. In five years, on or after September 26, 2017, we may redeem the debentures, in whole or in part, at their principal amount plus accrued and unpaid interest to, but excluding, the date of redemption; provided that if the debentures are not redeemed in whole, at least $25 million aggregate principal amount of the debentures must remain outstanding after giving effect to such redemption. The debentures may only be redeemed prior to September 26, 2017, in whole but not in part, upon the occurrence of certain tax events or certain rating agency events, as specified in the indenture governing the terms of the debentures. We entered into cross-currency interest rate swaps to convert the dollar-denominated principal and interest on the subordinated debentures we issued into yen-denominated obligations. By entering into these swaps, we economically converted our $450 million liability into a 35.3 billion yen liability and reduced the interest rate on this debt from 5.50% in dollars to 4.41% in yen. The swaps will expire after the initial five-year non-callable period for the debentures. In October 2012, the underwriters exercised their option, pursuant to the underwriting agreement, to purchase an additional $50 million principal amount of the debentures discussed above. We entered into a cross-currency interest rate swap to economically convert this $50 million liability into a 3.9 billion yen liability and reduce the interest rate from 5.50% in dollars to 4.42% in yen. The swap will expire after the initial five-year non-callable period for the debentures.
	In February 2012, the Parent Company issued two series of senior notes totaling $750 million through a U.S. public debt offering. The first series, which totaled $400 million, bears interest at a fixed rate of 2.65% per annum, payable semiannually, and has a five-year maturity. The second series, which totaled $350 million, bears interest at a fixed rate of 4.00% per annum, payable semiannually, and has a 10-year maturity. These notes are redeemable at our option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the principal amount of the notes or (ii) the present value of the remaining scheduled payments of principal and interest to be redeemed, discounted to the redemption date, plus accrued and unpaid interest. We entered into cross-currency interest rate swaps to reduce interest expense by converting the dollar-denominated principal and interest on the senior notes we issued into yen-denominated obligations. By entering into these swaps, we economically converted our $400 million liability into a 30.9 billion yen liability and reduced the interest rate on this debt from 2.65% in dollars to 1.22% in yen. We also economically converted our $350 million liability into a 27.0 billion yen liability and reduced the interest rate on this debt from 4.00% in dollars to 2.07% in yen. In July 2012, the Parent Company issued $250 million of senior notes that are an addition to the original first series of senior notes issued in February 2012. These notes have a five-year maturity and a fixed rate of 2.65% per annum, payable semiannually.
	In July 2011, the Parent Company issued three series of Samurai notes totaling 50 billion yen through a public debt offering. The first series, which totaled 28.7 billion yen, and the third series, which totaled 5.5 billion yen, were redeemed in July 2014. The second series, which totaled 15.8 billion yen, bears interest at a fixed rate of 1.84% per annum, payable semiannually, and has a five-year maturity. These Samurai notes are not available to U.S. persons.
	In 2010 and 2009, we issued senior notes through U.S. public debt offerings; the details of these notes are as follows. In August 2010, we issued $450 million and $300 million of senior notes that have 30-year and five-year maturities, respectively. In December 2009, we issued $400 million of senior notes that have a 30-year maturity. In May 2009, we issued $850 million of senior notes that have a 10-year maturity. These senior notes pay interest semiannually and are redeemable at our option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the principal amount of the notes or (ii) the present value of the remaining scheduled payments of principal and interest to be redeemed, discounted to the redemption date, plus accrued and unpaid interest.
	In September 2006, the Parent Company issued a tranche of Uridashi notes totaling 10 billion yen with a 10-year maturity. These Uridashi notes pay interest semiannually, may only be redeemed prior to maturity upon the occurrence of a tax event as specified in the respective bond agreement and are not available to U.S. persons. During 2009, we extinguished 2.0 billion yen (par value) of these Uridashi notes by buying the notes on the open market at a cost of 1.4 billion yen, yielding a gain of .6 billion yen.
	For our yen-denominated notes and loans, the principal amount as stated in dollar terms will fluctuate from period to period due to changes in the yen/dollar exchange rate. We have designated the majority of our yen-denominated notes payable as a nonderivative hedge of the foreign currency exposure of our investment in Aflac Japan.
	The aggregate contractual maturities of notes payable during each of the years after December 31, 2014, are as follows:
	(In millions)	Long-term				Capitalized				Total
		Debt				Lease				Notes
						Obligations				Payable
	2015		$	424			$	4			$	428
	2016		197				4				201
	2017		650				3				653
	2018		0				2				2
	2019		850				1				851
	Thereafter		3,150				0				3,150
	Total		$	5,271			$	14			$	5,285
	In October 2014, the Parent Company and Aflac entered into a 364-day uncommitted bilateral line of credit that provides for borrowings in the amount of $100 million. Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period. There are no related facility fees, upfront expense or financial covenant requirements. Borrowings under this credit agreement may be used for general corporate purposes. As of December 31, 2014, we did not have any borrowings outstanding under our $100 million credit agreement. Borrowings under the financing agreement will mature no later than three months after the last drawdown date of October 15, 2015.
	The Parent Company and Aflac have a senior unsecured revolving credit facility agreement with a syndicate of financial institutions that provides for borrowings in the amount of 50 billion yen. This credit agreement provides for borrowings in Japanese yen or the equivalent of Japanese yen in U.S. dollars on a revolving basis. Borrowings will bear interest at LIBOR plus the applicable margin of 1.125%. In addition, the Parent Company and Aflac are required to pay a facility fee of .125% on the commitments. As of December 31, 2014, we did not have any borrowings outstanding under our 50 billion yen revolving credit agreement. Borrowings under the credit agreement may be used for general corporate purposes, including a capital contingency plan for our Japanese operations. Borrowings under the financing agreement mature at the termination date of the credit agreement. The agreement requires compliance with certain financial covenants on a quarterly basis. This credit agreement will expire on the earlier of March 29, 2018, or the date of termination of the commitments upon an event of default as defined in the agreement.
	We were in compliance with all of the covenants of our notes payable and lines of credit at December 31, 2014. No events of default or defaults occurred during 2014 and 2013.

INCOME_TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
INCOME TAXES	NCOME TAXES
	The components of income tax expense (benefit) applicable to pretax earnings for the years ended December 31 were as follows:
	(In millions)	Foreign				U.S.				Total
	2014:00:00
	Current		$	995			$	84			$	1,079
	Deferred		125				336				461
	Total income tax expense		$	1,120			$	420			$	1,540
	2013:00:00
	Current		$	934			$	302			$	1,236
	Deferred		299				123				422
	Total income tax expense		$	1,233			$	425			$	1,658
	2012:00:00
	Current		$	513			$	303			$	816
	Deferred		950				(330		)		620
	Total income tax expense		$	1,463			$	(27	)		$	1,436
	Japan enacted an income tax rate reduction effective for fiscal years beginning after March 31, 2012. The rate was reduced to 33.3% effective April 1, 2012, and an additional reduction to 30.8% became effective January 1, 2015. The estimated reversal of the temporary differences resulted in a decrease to deferred taxes in Japan of $744 million and a corresponding increase in U.S. deferred taxes, due to the loss of foreign tax credits, of $744 million as of December 31, 2011. Based on the actual reversal pattern of these temporary differences, we revised our estimate of the impact of the tax rate reduction, resulting in an increase to deferred taxes in Japan of $374 million and a corresponding decrease in U.S. deferred taxes of $374 million as of December 31, 2012.
	Income tax expense in the accompanying statements of earnings varies from the amount computed by applying the expected U.S. tax rate of 35% to pretax earnings. The principal reasons for the differences and the related tax effects for the years ended December 31 were as follows:
	(In millions)	2014				2013				2012
	Income taxes based on U.S. statutory rates		$	1,572			$	1,685			$	1,506
	Utilization of foreign tax credit		(32		)		(37		)		(53		)
	Nondeductible expenses		5				6				8
	Other, net		(5		)		4				(25		)
	Income tax expense		$	1,540			$	1,658			$	1,436
	Total income tax expense for the years ended December 31 was allocated as follows:
	(In millions)	2014				2013				2012
	Statements of earnings		$	1,540			$	1,658			$	1,436
	Other comprehensive income (loss):
	Unrealized foreign currency translation gains (losses) during period		(419		)		253				363
	Unrealized gains (losses) on investment securities:
	Unrealized holding gains (losses) on investment		2,237				(904		)		904
	securities during period
	Reclassification adjustment for realized (gains) losses		19				19				(174		)
	on investment securities included in net earnings
	Unrealized gains (losses) on derivatives during period		(3		)		(4		)		(8		)
	Pension liability adjustment during period		(31		)		55				(7		)
	Total income tax expense (benefit) related to items of		1,803				(581		)		1,078
	other comprehensive income (loss)
	Additional paid-in capital (exercise of stock options)		(7		)		(8		)		(12		)
	Total income taxes		$	3,336			$	1,069			$	2,502
	The tax effect on other comprehensive income (loss) shown in the table above included a deferred income tax expense of $614 million in 2013 and $492 million in 2012, related to certain dollar-denominated investments that Aflac Japan maintained on behalf of Aflac U.S. As discussed in Note 1, prior to October 1, 2013, there was no translation adjustment to record in pretax other comprehensive income for the portfolio when the yen/dollar exchange rate changed, however deferred tax expense or benefit associated with the foreign exchange translation gains or losses on these dollar-denominated investments is recognized in total income tax expense on other comprehensive income until the securities mature or are sold. Excluding the tax amounts for these dollar-denominated investments from total taxes on other comprehensive income would result in an effective income tax rate on pretax other comprehensive income (loss) of 31% in 2013 and 32% in 2012.
	The income tax effects of the temporary differences that gave rise to deferred income tax assets and liabilities as of December 31 were as follows:
	(In millions)	2014				2013
	Deferred income tax liabilities:
	Deferred policy acquisition costs		$	2,209			$	2,406
	Unrealized gains on investment securities		2,584				533
	Premiums receivable		139				134
	Policy benefit reserves		1,376				1,451
	Depreciation		51				54
	Other		20				22
	Total deferred income tax liabilities		6,379				4,600
	Deferred income tax assets:
	Other basis differences in investment securities		1,331				1,129
	Unfunded retirement benefits		16				16
	Other accrued expenses		4				23
	Policy and contract claims		99				111
	Foreign currency loss on Japan branch		327				189
	Deferred compensation		226				182
	Capital loss carryforwards		26				514
	Total deferred income tax assets		2,029				2,164
	Net deferred income tax liability		4,350				2,436
	Current income tax liability		943				1,282
	Total income tax liability		$	5,293			$	3,718
	Under U.S. income tax rules, only 35% of non-life operating losses can be offset against life insurance taxable income each year. For current U.S. income tax purposes, there were non-life operating loss carryforwards of $18 million, $17 million, $2 million and $1 million expiring in 2031, 2032, 2033 and 2034, respectively, and no tax credit carryforwards available at December 31, 2014. The Company has capital loss carryforwards of $73 million available to offset capital gains, which expire in 2016.
	We file federal income tax returns in the United States and Japan as well as state or prefecture income tax returns in various jurisdictions in the two countries. U.S. federal income tax returns for years before 2010 are no longer subject to examination. In Japan, the National Tax Agency (NTA) has completed exams through tax year 2011.
A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows for the years ended December 31:
(In millions)		2014			2013
Balance, beginning of year		$	328		$	401
Additions for tax positions of prior years		2			1
Reductions for tax positions of prior years		(21		)	(74		)
Balance, end of year		$	309		$	328
Included in the balance of the liability for unrecognized tax benefits at December 31, 2014, are $307 million of tax positions for which the ultimate deductibility is highly certain, but for which there is uncertainty about the timing of such deductibility, compared with $327 million at December 31, 2013. Because of the impact of deferred tax accounting, other than interest and penalties, the disallowance of the shorter deductibility period would not affect the annual effective tax rate, but would accelerate the payment of cash to the taxing authority to an earlier period. The Company has accrued approximately $2 million as of December 31, 2014, for permanent uncertainties, which if reversed would not have a material effect on the annual effective rate.
The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense. We recognized approximately $11 million in interest and penalties in 2014 and 2013, and $7 million in 2012. The Company has accrued approximately $30 million for the payment of interest and penalties as of December 31, 2014, compared with $26 million a year ago.
As of December 31, 2014, there were no material uncertain tax positions for which the total amounts of unrecognized tax benefits will significantly increase or decrease within the next 12 months.

SHAREHOLDERS_EQUITY

SHAREHOLDERS' EQUITY	12 Months Ended
	Dec. 31, 2014
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 years ended December 31.
	(In thousands of shares)	2014		2013		2012
	Common stock - issued:
	Balance, beginning of period	667,046		665,239		663,639
	Exercise of stock options and issuance of restricted shares	1,086		1,807		1,600
	Balance, end of period	668,132		667,046		665,239
	Treasury stock:
	Balance, beginning of period	207,633		197,453		197,329
	Purchases of treasury stock:
	Open market	19,660		13,212		1,948
	Other	157		222		360
	Dispositions of treasury stock:
	Shares issued to AFL Stock Plan	-1,251		-1,365		-1,670
	Exercise of stock options	-391		-1,734		-387
	Other	-121		-155		-127
	Balance, end of period	225,687		207,633		197,453
	Shares outstanding, end of period	442,445		459,413		467,786
	Outstanding share-based awards are excluded from the calculation of weighted-average shares used in the computation of basic 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 at December 31:
	(In thousands)	2014					2013					2012
	Anti-dilutive share-based awards		1,215					2,198					5,880
	The weighted-average shares used in calculating earnings per share for the years ended December 31 were as follows:
	(In thousands of shares)	2014			2013			2012
	Weighted-average outstanding shares used for calculating basic EPS	451,204			464,502			466,868
	Dilutive effect of share-based awards	2,796			2,906			2,419
	Weighted-average outstanding shares used for calculating diluted EPS	454,000			467,408			469,287
	Share Repurchase Program: During 2014, we purchased 19.7 million shares of our common stock in the open market, compared with 13.2 million shares in 2013 and 1.9 million shares in 2012. As of December 31, 2014, a remaining balance of 29.6 million shares of our common stock was available for purchase under share repurchase authorizations by our board of directors.
	Voting Rights: In accordance with the Parent Company's articles of incorporation, shares of common stock are generally entitled to one vote per share until they have been held by the same beneficial owner for a continuous period of 48 months, at which time they become entitled to 10 votes per share.
	Reclassifications from Accumulated Other Comprehensive Income
	The table below is a reconciliation of accumulated other comprehensive income by component for the years ended December 31.
	Changes in Accumulated Other Comprehensive Income
	2014
	(In millions)	Unrealized Foreign						Unrealized						Unrealized				Pension				Total
		Currency Translation						Gains (Losses)						Gains (Losses)				Liability
		Gains (Losses)						on Investment Securities						on Derivatives				Adjustment
	Balance, beginning of period		$	(1,505	)				$	1,035					$	(12	)		$	(81	)		$	(563	)
	Other comprehensive		(1,036		)				3,672						(14		)		(44		)		2,578
	income before
	reclassification
	Amounts reclassified from		0						(35		)				0				(1		)		(36		)
	accumulated other
	comprehensive income
	Net current-period other		(1,036		)				3,637						(14		)		(45		)		2,542
	comprehensive
	income
	Balance, end of period		$	(2,541	)				$	4,672					$	(26	)		$	(126	)		$	1,979
	All amounts in the table above are net of tax.
	2013
	(In millions)	Unrealized Foreign						Unrealized						Unrealized				Pension Liability Adjustment				Total
		Currency Translation						Gains (Losses)						Gains (Losses)
		Gains (Losses)						on Investment Securities						on Derivatives
	Balance, beginning of period		$	333					$	2,570					$	(5	)		$	(183	)		$	2,715
	Other comprehensive		(1,833		)				(1,499		)				(7		)		92				(3,247		)
	income before
	reclassification
	Amounts reclassified from		(5		)				(36		)				0				10				(31		)
	accumulated other
	comprehensive income
	Net current-period other		(1,838		)				(1,535		)				(7		)		102				(3,278		)
	comprehensive
	income
	Balance, end of period		$	(1,505	)				$	1,035					$	(12	)		$	(81	)		$	(563	)
	All amounts in the table above are net of tax.
	The table below summarizes the amounts reclassified from each component of accumulated other comprehensive income based on source for the years ended December 31.
Reclassifications Out of Accumulated Other Comprehensive Income
(In millions)	2014
Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income					Affected Line Item in the
						Statements of Earnings
Unrealized gains (losses) on available-for-sale		$	57			Sales and redemptions
securities
		(3		)		Other-than-temporary impairment
						losses realized
		54				Total before tax
		(19		)		Tax (expense) or benefit(1)
		$	35			Net of tax
Amortization of defined benefit pension items:
Actuarial gains (losses)		$	(15	)		Acquisition and operating expenses(2)
Prior service (cost) credit		17				Acquisition and operating expenses(2)
		(1		)		Tax (expense) or benefit(1)
		$	1			Net of tax
Total reclassifications for the period		$	36			Net of tax
(1) Based on 35% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see
Note 14 for additional details).
(In millions)	2013
Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income					Affected Line Item in the
						Statements of Earnings
Unrealized foreign currency translation gains		$	7			Sales and redemptions
(losses)
		(2		)		Tax (expense) or benefit(1)
		$	5			Net of tax
Unrealized gains (losses) on available-for-sale		$	255			Sales and redemptions
securities
		(199		)		Other-than-temporary impairment
						losses realized
		56				Total before tax
		(20		)		Tax (expense) or benefit(1)
		$	36			Net of tax
Amortization of defined benefit pension items:
Actuarial gains (losses)		$	(19	)		Acquisition and operating expenses(2)
Prior service (cost) credit		4				Acquisition and operating expenses(2)
		5				Tax (expense) or benefit(1)
		$	(10	)		Net of tax
Total reclassifications for the period		$	31			Net of tax
(1) Based on 35% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see
Note 14 for additional details).

SHAREBASED_COMPENSATION

SHARE-BASED COMPENSATION	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
SHARE-BASED COMPENSATION	SHARE-BASED COMPENSATION
	As of December 31, 2014, the Company has outstanding share-based awards under two long-term incentive compensation plans.
	The first plan, which expired in February 2007, is a stock option plan which allowed grants for incentive stock options (ISOs) to employees and non-qualifying stock options (NQSOs) to employees and non-employee directors. The options have a term of 10 years. The exercise price of options granted under this plan is equal to the fair market value of a share of the Company's common stock at the date of grant. Options granted before the plan's expiration date remain outstanding in accordance with their terms.
	The second long-term incentive compensation plan allows awards to Company employees for ISOs, 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. 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 December 31, 2014, approximately 11.2 million shares were available for future grants under this plan, and the only performance-based awards issued and outstanding were restricted stock awards.
	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 presents the impact of the expense recognized in connection with share-based awards for the periods ended December 31.
	(In millions, except for per-share amounts)	2014						2013						2012
	Impact on earnings from continuing operations		$	41					$	37					$	37
	Impact on earnings before income taxes		41						37						37
	Impact on net earnings		28						25						26
	Impact on net earnings per share:
	Basic		$	0.06					$	0.05					$	0.06
	Diluted		0.06						0.05						0.06
	We estimate the fair value of each stock option granted using the Black-Scholes-Merton multiple option approach. Expected volatility is based on historical periods generally commensurate with the estimated terms of the options. We use historical data to estimate option exercise and termination patterns within the model. Separate groups of employees that have similar historical exercise patterns are stratified and considered separately for valuation purposes. The expected term of options granted is derived from the output of our option model and represents the weighted-average period of time that options granted are expected to be outstanding. We base the risk-free interest rate on the Treasury note rate with a term comparable to that of the estimated term of the options. The weighted-average fair value of options at their grant date was $16.24 per share for 2014, compared with $14.25 for 2013 and $16.84 in 2012. The following table presents the assumptions used in valuing options granted during the years ended December 31.
		2014				2013				2012
	Expected term (years)		6.3				6.6				6.5
	Expected volatility		30	%			34	%			38	%
	Annual forfeiture rate		2.7				1.6				1.6
	Risk-free interest rate		2.8				1.8				2.1
	Dividend yield		2.3				2.6				1.3
	The following table summarizes stock option activity.
	(In thousands of shares)	Stock					Weighted-Average
		Option					Exercise Price
		Shares					Per Share
	Outstanding at December 31, 2011		14,563					$	42.76
	Granted in 2012		784					47.25
	Canceled in 2012		(134	)				48.59
	Exercised in 2012		(2,476	)				32.27
	Outstanding at December 31, 2012		12,737					45
	Granted in 2013		703					52.86
	Canceled in 2013		(179	)				44.79
	Exercised in 2013		(3,281	)				40.52
	Outstanding at December 31, 2013		9,980					47.03
	Granted in 2014		678					61.81
	Canceled in 2014		(115	)				52.01
	Exercised in 2014		(1,236	)				41.04
	Outstanding at December 31, 2014		9,307					$	48.84
	(In thousands of shares)	2014					2013					2012
	Shares exercisable, end of year		7,497					8,042					10,635
	The following table summarizes information about stock options outstanding and exercisable at December 31, 2014.
	(In thousands of shares)										Options Outstanding										Options Exercisable
		Range of									Stock Option					Wgtd.-Avg.		Wgtd.-Avg.			Stock Option		Wgtd.-Avg.
		Exercise Prices									Shares					Remaining		Exercise			Shares		Exercise
		Per Share									Outstanding					Contractual		Price			Exercisable		Price
																Life (Yrs.)		Per Share					Per Share
		$	14.99		-	$	43.07					2,028					3.8		$	34.46		1,945		$	34.2
		43.28			-	47.25						2,144					3.1		45.93			2,046		45.93
		47.33			-	51.91						1,883					5.4		48.97			1,109		48.86
		52.14			-	61.81						2,479					4.5		58.65			2,296		58.79
		61.84			-	67.67						773					8.5		62.85			101		64.63
		$	14.99		-	$	67.67					9,307					4.5		$	48.84		7,497		$	47.51
	The aggregate intrinsic value represents the difference between the exercise price of the stock options and the quoted closing common stock price of $61.09 as of December 31, 2014, for those awards that have an exercise price currently below the closing price. As of December 31, 2014, the aggregate intrinsic value of stock options outstanding was $116 million, with a weighted-average remaining term of 4.5 years. The aggregate intrinsic value of stock options exercisable at that same date was $103 million, with a weighted-average remaining term of 3.6 years.
	The following table summarizes stock option activity during the years ended December 31.
	(In millions)	2014						2013						2012
	Total intrinsic value of options exercised		$	25					$	66					$	41
	Cash received from options exercised		39						113						35
	Tax benefit realized as a result of options exercised and		17						30						24
	restricted stock releases
	The value of restricted stock awards is based on the fair market value of our common stock at the date of grant. The following table summarizes restricted stock activity during the years ended December 31.
	(In thousands of shares)	Shares					Weighted-Average
							Grant-Date
							Fair Value
							Per  Share
	Restricted stock at December 31, 2011		1,350					$	40.92
Granted in 2012		637					48.18
Canceled in 2012		(56	)				48.22
Vested in 2012		(568	)				26.13
Restricted stock at December 31, 2012		1,363					50.19
Granted in 2013		782					52.77
Canceled in 2013		(56	)				48.63
Vested in 2013		(418	)				47.49
Restricted stock at December 31, 2013		1,671					52.12
Granted in 2014		584					62.12
Canceled in 2014		(27	)				52.66
Vested in 2014		(348	)				56.95
Restricted stock at December 31, 2014		1,880					$	54.33
As of December 31, 2014, total compensation cost not yet recognized in our financial statements related to restricted stock awards was $45 million, of which $20 million (849 thousand shares) was related to restricted stock awards with a performance-based vesting condition. We expect to recognize these amounts over a weighted-average period of approximately 1.2 years. There are no other contractual terms covering restricted stock awards once vested.

STATUTORY_ACCOUNTING_AND_DIVID

STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS	12 Months Ended
	Dec. 31, 2014
Statutory Accounting Practices Disclosure [Abstract]
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS	STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS
	Our insurance subsidiaries are required to report their results of operations and financial position to state insurance regulatory authorities on the basis of statutory accounting practices prescribed or permitted by such authorities. Statutory accounting practices primarily differ from U.S. GAAP by charging policy acquisition costs to expense as incurred, establishing future policy benefit liabilities using different actuarial assumptions as well as valuing investments and certain assets and accounting for deferred taxes on a different basis.
	Aflac, the Company's most significant insurance subsidiary, reports statutory financial statements that are prepared on the basis of accounting practices prescribed or permitted by the Nebraska Department of Insurance (NEDOI). The NEDOI recognizes statutory accounting principles and practices prescribed or permitted by the state of Nebraska for determining and reporting the financial condition and results of operations of an insurance company, and for determining a company's solvency under Nebraska insurance law. The National Association of Insurance Commissioners' (NAIC) Accounting Practices and Procedures Manual (SAP) has been adopted by the state of Nebraska as a component of those prescribed or permitted practices. Additionally, the Director of the NEDOI has the right to permit other specific practices which deviate from prescribed practices. Aflac has been given explicit permission by the Director of the NEDOI for two such permitted practices. These permitted practices, which do not impact the calculation of net income on a statutory basis or prevent the triggering of a regulatory event in the Company's risk-based capital calculation, are as follows:
	•	Aflac has reported as admitted assets the refundable lease deposits on the leases of commercial office space which house Aflac Japan's sales operations. These lease deposits are unique and part of the ordinary course of doing business in the country of Japan; these assets would be non-admitted under SAP.
	•	Aflac utilized book value accounting for certain guaranteed separate account funding agreements instead of fair value accounting as required by SAP. The underlying separate account assets had an unrealized gain of $35 million as of December 31, 2013. In June 2014, the guaranteed separate account funding agreements were settled and at that time, Aflac's separate account assets were transferred to the general account.
	A reconciliation of Aflac's capital and surplus between SAP and practices permitted by the state of Nebraska is shown below:
	(In millions)	2014				2013
	Capital and surplus, Nebraska state basis		$	10,839			$	9,630
	State Permitted Practice:
	Refundable lease deposits – Japan		(36		)		(41		)
	Separate Account Funding Agreements		0				35
	Capital and surplus, NAIC basis		$	10,803			$	9,624
	As of December 31, 2014, Aflac's capital and surplus significantly exceeded the required company action level capital and surplus of $1.2 billion. As determined on a U.S. statutory accounting basis, Aflac's net income was $2.4 billion in 2014 and 2013 and $2.3 billion in 2012.
	Aflac Japan must report its results of operations and financial position to the Japanese Financial Services Agency (FSA) on a Japanese regulatory accounting basis as prescribed by the FSA. Capital and surplus of the Japan branch, based on Japanese regulatory accounting practices, was $5.6 billion at December 31, 2014, compared with $4.2 billion at December 31, 2013. Japanese regulatory accounting practices differ in many respects from U.S. GAAP. Under Japanese regulatory accounting practices, policy acquisition costs are expensed immediately; deferred income tax liabilities are recognized on a different basis; policy benefit and claim reserving methods and assumptions are different; premium income is recognized on a cash basis; reinsurance is recognized on a different basis; and investments can have a separate accounting classification and treatment referred to as “policy reserve matching bonds,” or “PRM.”
	The Parent Company depends on its subsidiaries for cash flow, primarily in the form of dividends and management fees. Consolidated retained earnings in the accompanying financial statements largely represent the undistributed earnings of our insurance subsidiary. Amounts available for dividends, management fees and other payments to the Parent Company by its insurance subsidiary may fluctuate due to different accounting methods required by regulatory authorities. These payments are also subject to various regulatory restrictions and approvals related to safeguarding the interests of insurance policyholders. Our insurance subsidiary must maintain adequate risk-based capital for U.S. regulatory authorities and our Japan branch must maintain adequate solvency margins for Japanese regulatory authorities. Additionally, the maximum amount of dividends that can be paid to the Parent Company by Aflac without prior approval of Nebraska's director of insurance is the greater of the net income from operations, which excludes net realized investment gains, for the previous year determined under statutory accounting principles, or 10% of statutory capital and surplus as of the previous year-end. Dividends declared by Aflac during 2015 in excess of $2.4 billion would require such approval. Aflac declared dividends of $1.5 billion during 2014.
	A portion of Aflac Japan earnings, as determined on a Japanese regulatory accounting basis, can be repatriated each year to Aflac U.S. after complying with solvency margin provisions and satisfying various conditions imposed by Japanese regulatory authorities for protecting policyholders. Profit repatriations to the United States can fluctuate due to changes in the amounts of Japanese regulatory earnings. Among other items, factors affecting regulatory earnings include Japanese regulatory accounting practices and fluctuations in currency translation of Aflac Japan's dollar-denominated investments and related investment income into yen. Profits repatriated by Aflac Japan to Aflac U.S. were as follows for the years ended December 31:
		In Dollars											In Yen
	(In millions of dollars and billions of yen)	2014				2013				2012			2014		2013		2012
	Profit repatriation		$	1,704			$	771			$	422		181.4		76.8		33.1
	We had entered into foreign exchange forwards and options as part of an economic hedge on 52.5 billion yen of profit repatriation received in July 2014 and 50.0 billion yen of repatriation received in December 2014, resulting in $7 million and $45 million of additional funds received, respectively, when the yen was exchanged into dollars. As of December 31, 2014, we had foreign exchange forwards as part of a hedging strategy on 157.5 billion yen of future profit repatriation.

BENEFIT_PLANS

BENEFIT PLANS	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
BENEFIT PLANS	BENEFIT PLANS
	Pension and Other Postretirement Plans
	We have funded defined benefit plans in Japan and the United States, which cover substantially all of our full-time employees. Additionally, we maintain 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. Effective October 1, 2013, the U.S. tax-qualified defined benefit plan was frozen to new employees hired on or after October 1, 2013 and to employees rehired on or after October 1, 2013. During the fourth quarter of 2013, active participants in this plan were given the option to exit the benefit plan and receive a nonelective 401(k) employer contribution. Additionally, effective January 1, 2015, the U.S. non-qualified supplemental retirement plan was frozen to new participants.
	We provide 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. On October 1, 2013, a change was made to postretirement medical benefits to limit the eligibility for the benefits beginning January 1, 2014 to include the following: (1) active employees whose age plus service, in years, equals or exceeds 80 (rule of 80); (2) active employees who are age 55 or older and have met the 15 years of service requirement; (3) active employees who will meet the rule of 80 in the next five years; (4) active employees who are age 55 or older and who will meet the 15 years of service requirement within the next five years; and (5) current retirees. Effective October 1, 2013, this change was accounted for as a negative plan amendment and resulted in a reduction to the postretirement benefit obligation of approximately $51 million, with an offset to accumulated other comprehensive income (AOCI). Starting in the fourth quarter of 2013, this reduction is being amortized as a reduction to net periodic benefit cost over three years. The postretirement plan obligation was remeasured using a discount rate of 4.75% as of October 1, 2013. For certain employees and former employees, additional coverage is provided for all medical expenses for life.
	Information with respect to our benefit plans' assets and obligations as of December 31 was as follows:
			Pension Benefits																						Other
			Japan											U.S.											Postretirement Benefits
	(In millions)		2014					2013						2014					2013						2014					2013
	Projected benefit obligation:
	Benefit obligation, beginning of year			$	270				$	313					$	601				$	613					$	46				$	98
	Service cost			15					16						20					22						1					5
	Interest cost			9					10						38					23						2					3
	Plan amendments			0					0						0					(4		)				0					(51		)
	Actuarial (gain) loss			21					(3		)				74					(37		)				(3		)			(7		)
	Benefits and expenses paid			(9		)			(8		)				(16		)			(16		)				(2		)			(2		)
	Effect of foreign exchange			(39		)			(58		)				0					0						0					0
	rate changes
	Benefit obligation, end of year			267					270						717					601						44					46
	Plan assets:
	Fair value of plan assets,			182					187						313					261						0					0
	beginning of year
	Actual return on plan assets			12					13						26					39						0					0
	Employer contributions			24					26						18					29						2					2
	Benefits and expenses paid			(9		)			(8		)				(16		)			(16		)				(2		)			(2		)
	Effect of foreign exchange			(26		)			(36		)				0					0						0					0
	rate changes
	Fair value of plan assets, end of year			183					182						341					313						0					0
	Funded status of the plans(1)			$	(84	)			$	(88	)				$	(376	)			$	(288	)				$	(44	)			$	(46	)
	Amounts recognized in accumulated other
	comprehensive income:
	Net actuarial (gain) loss			$	40				$	33					$	167				$	111					$	19				$	25
	Prior service (credit) cost			(2		)			(2		)				(4		)			(4		)				(28		)			(45		)
	Transition obligation			0					1						0					0						0					0
	Total included in accumulated			$	38				$	32					$	163				$	107					$	(9	)			$	(20	)
	other comprehensive income
	Accumulated benefit obligation			$	235				$	239					$	611				$	514					N/A			(2)		N/A			(2)
	(1) Recognized in other liabilities in the consolidated balance sheets
	(2) Not applicable
		Pension Benefits																				Other
		Japan										U.S.										Postretirement Benefits
		2014			2013			2012				2014			2013			2012				2014			2013			2012
	Weighted-average actuarial assumptions:
	Discount rate - net periodic benefit cost	2.25	%		2.25	%		2.25	%			4.75	%		4.25	%		4.75	%			4.75	%		4.25	%		4.75	%
	Discount rate - benefit obligations	1.75			2.25			2.25				4.5			4.75			4.25				4.5			4.75			4.25
	Expected long-term return on plan assets	2			2			2.5				7.5			7.5			7.5				N/A		(1)	N/A		(1)	N/A		(1)
	Rate of compensation increase	N/A		(1)	N/A		(1)	N/A		(1)		4			4			4				N/A		(1)	N/A		(1)	N/A		(1)
	Health care cost trend rates	N/A		(1)	N/A		(1)	N/A		(1)		N/A		(1)	N/A		(1)	N/A		(1)		5.7		(2)	6.4		(2)	5.7		(2)
	(1) Not applicable
	(2)For the years 2014, 2013 and 2012, the health care cost trend rates are expected to trend down to 4.6% in 78 years, 4.6% in
	78 years, and 4.7% in 79 years, respectively.
	We determine our discount rate assumption for our pension retirement obligations based on indices for AA corporate bonds with an average duration of approximately 20 years for the Japan pension plans and 17 years for the U.S. pension plans, and determination of the U.S. pension plans discount rate utilizes the 85-year extrapolated yield curve. In Japan, participant salary and future salary increases are not factors in determining pension benefit cost or the related pension benefit obligation.
	We base our assumption for the long-term rate of return on assets on historical trends (10-year or longer historical rates of return for the Japanese plan assets and 15-year historical rates of return for the U.S. plan assets), expected future market movement, as well as the portfolio mix of securities in the asset portfolio including, but not limited to, style, class and equity and fixed income allocations. In addition, our consulting actuaries evaluate our assumptions for long-term rates of return under Actuarial Standards of Practice (ASOP). Under the ASOP, the actual portfolio type, mix and class is modeled to determine a best estimate of the long-term rate of return. We in turn use those results to further validate our own assumptions.
	Assumed health care cost trend rates have a significant effect on the amounts reported for the health care plan. A one-percentage point increase and decrease in assumed health care cost trend rates would have the following effects as of December 31, 2014:
	(In millions)
	One percentage point increase:
	Increase in total service and interest costs			$	0
	Increase in postretirement benefit obligation			3
	One percentage point decrease:
	Decrease in total service and interest costs			$	0
	Decrease in postretirement benefit obligation			2
	Components of Net Periodic Benefit Cost
	Pension and other postretirement benefit expenses, included in acquisition and operating expenses in the consolidated statements of earnings for the years ended December 31, included the following components:
			Pension Benefits																																		Other
				Japan																	U.S.																Postretirement Benefits
(In millions)		2014						2013						2012						2014						2013						2012				2014				2013				2012
Service cost			$	15					$	16					$	18					$	20					$	22					$	18			$	1			$	5			$	6
Interest cost			9						10						7						38						23						24				2				3				4
Expected return on plan			(4		)				(3		)				(4		)				(20		)				(17		)				(16		)		0				0				0
assets
Amortization of net actuarial			1						2						3						11						15						11				3				2				1
loss
Amortization of prior service			0						0						0						0						0						0				(17		)		(4		)		0
cost (credit)
Net periodic (benefit) cost			$	21					$	25					$	24					$	49					$	43					$	37			$	(11	)		$	6			$	11
Changes in Accumulated Other Comprehensive Income
The following table summarizes the amounts recognized in other comprehensive loss (income) for the years ended December 31:
		Pension Benefits																																		Other
		Japan																		U.S.																Postretirement Benefits
(In millions)		2014						2013						2012						2014						2013						2012				2014				2013				2012
Net actuarial loss (gain)			$	12					$	(14	)				$	(10	)				$	67					$	(59	)				$	45			$	(3	)		$	(7	)		$	5
Amortization of net actuarial loss			(1		)				(2		)				(3		)				(11		)				(15		)				(11		)		(3		)		(2		)		(1		)
Prior service cost (credit)			0						0						0						0						(4		)				(1		)		0				(51		)		2
Amortization of prior			0						0						0						0						0						0				17				4				0
service cost
Total			$	11					$	(16	)				$	(13	)				$	56					$	(78	)				$	33			$	11			$	(56	)		$	6
Prior service credits of $51 million were incurred in 2013 for the plan amendment related to the change in eligibility for postretirement medical benefits mentioned above. No transition obligations arose during 2014, and the transition obligations amortized to expense were immaterial for the years ended December 31, 2014, 2013 and 2012. Amortization of actuarial losses to expense in 2015 is estimated to be $1 million for the Japanese plans, $15 million for the U.S. plans and $2 million for the other postretirement benefits plan. Amortization of prior service credits in 2015 is estimated to be $17 million for the other postretirement benefits plan due to the negative plan amendment in 2013. The amortization of prior service costs and credits for other plans and transition obligations for all plans is expected to be negligible in 2015.
Benefit Payments
The following table provides expected benefit payments, which reflect expected future service, as appropriate.
		Pension Benefits											Other
(In millions)		Japan					U.S.						Postretirement Benefits
2015			$	7				$	20					$	2
2016			11					21						2
2017			8					28						3
2018			7					26						3
2019			9					27						4
2020-2024			63					159						22
Funding
We plan to make contributions of $19 million to the Japanese funded defined benefit plan and $10 million to the U.S. funded defined benefit plan in 2015. The funding policy for our non-qualified supplemental defined benefit pension plans and other postretirement benefits plan is to contribute the amount of the benefit payments made during the year.
Plan Assets
The investment objective of our Japanese and U.S. funded defined benefit plans is to preserve the purchasing power of the plan's assets and earn a reasonable inflation-adjusted rate of return over the long term. Furthermore, we seek to accomplish these objectives in a manner that allows for the adequate funding of plan benefits and expenses. In order to achieve these objectives, our goal is to maintain a conservative, well-diversified and balanced portfolio of high-quality equity, fixed-income and money market securities. As a part of our strategy, we have established strict policies covering quality, type and concentration of investment securities. For our Japanese plan, these policies include limitations on investments in derivatives including futures, options and swaps, and low-liquidity investments such as real estate, venture capital investments, and privately issued securities. For our U.S. plan, these policies prohibit investments in precious metals, limited partnerships, venture capital, and direct investments in real estate. We are also prohibited from trading on margin.
The plan fiduciaries for our funded defined benefit plans have developed guidelines for asset allocations reflecting a percentage of total assets by asset class, which are reviewed on an annual basis. Asset allocation targets as of December 31, 2014 were as follows:
		Japan Pension					U.S. Pension
Domestic equities			0	%				40	%
International equities			15					20
Fixed income securities			70					40
Other			15					0
Total			100	%				100	%
The following table presents the fair value of Aflac Japan's pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 2 in the fair value hierarchy, except cash and cash equivalents which are classified as Level 1.
(In millions)	2014						2013
Japan pension plan assets:
International equity securities		$	34					$	34
Fixed income securities:
Japanese bonds		72						60
International bonds		44						43
Mutual funds		0						21
Insurance contracts		22						24
Cash and cash equivalents		11						0
Total		$	183					$	182
The following table presents the fair value of Aflac U.S.'s pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 1 in the fair value hierarchy.
(In millions)	2014						2013
U.S. pension plan assets:
Mutual funds:
Large cap equity funds		$	116					$	110
Mid cap equity funds		14						19
Real estate equity funds		10						9
International equity funds		61						68
Fixed income bond funds		136						103
Aflac Incorporated common stock		4						4
Total		$	341					$	313
The fair values of our pension plan investments categorized as Level 1, consisting of mutual funds and common stock, are based on quoted market prices for identical securities traded in active markets that are readily and regularly available to us. The fair values of our pension plan investments classified as Level 2 are based on quoted prices for similar assets in markets that are not active, other inputs that are observable, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, and default rates, or other market-corroborated inputs.
401(k) Plan
The Company sponsors a 401(k) plan in which we match a portion of U.S. employees' contributions. The plan provides for salary reduction contributions by employees and, in 2014, 2013, and 2012, provided matching contributions by the Company of 50% of each employee's contributions which were not in excess of 6% of the employee's annual cash compensation.
On January 1, 2014, the Company began providing a nonelective contribution to the 401(k) plan of 2% of annual cash compensation for employees who elected to opt out of the future benefits of the U.S. defined benefit plan during the election period provided during the fourth quarter of 2013 and for new U.S. employees who started working for the Company after September 30, 2013.
The 401(k) contributions by the Company, included in acquisition and operating expenses in the consolidated statements of earnings, were $7 million in 2014 and $5 million in both 2013 and 2012. The plan trustee held approximately two million shares of our common stock for plan participants at December 31, 2014.
Stock Bonus Plan
Aflac U.S. maintains a stock bonus plan for eligible U.S. sales associates. Plan participants receive shares of Aflac Incorporated common stock based on their new annualized premium sales and their first-year persistency of substantially all new insurance policies. The cost of this plan, which was capitalized as deferred policy acquisition costs, amounted to $36 million in 2014, compared with $38 million in 2013 and 2012.

COMMITMENTS_AND_CONTINGENT_LIA

COMMITMENTS AND CONTINGENT LIABILITIES	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENT LIABILITIES	COMMITMENTS AND CONTINGENT LIABILITIES
	We have three outsourcing agreements with a technology and consulting corporation. The first agreement provides mainframe computer operations and support for Aflac Japan. It has a remaining term of one year and an aggregate remaining cost of 4.8 billion yen ($40 million using the December 31, 2014, exchange rate). The second agreement provides distributed mid-range server computer operations and support for Aflac Japan. It has a remaining term of one year and an aggregate remaining cost of 3.9 billion yen ($32 million using the December 31, 2014, exchange rate). The third agreement provides application maintenance and development services for Aflac Japan. It has a remaining term of three years and an aggregate remaining cost of 4.4 billion yen ($36 million using the December 31, 2014, exchange rate).
	We have an outsourcing agreement with a management consulting and technology services company to provide application maintenance and development services for our Japanese operation. The agreement has a remaining term of three years with an aggregate remaining cost of 3.8 billion yen ($31 million using the December 31, 2014, exchange rate).
	We have two outsourcing agreement with information technology and data services companies to provide application maintenance and development services for our Japanese operation. The first agreement has a remaining term of two years with an aggregate remaining cost of 2.3 billion yen ($19 million using the December 31, 2014, exchange rate). The second agreement has a remaining term of three years with an aggregate remaining cost of 2.3 billion yen ($19 million using the December 31, 2014, exchange rate).
	We lease office space and equipment under agreements that expire in various years through 2022. Future minimum lease payments due under non-cancelable operating leases at December 31, 2014, were as follows:
	(In millions)
	2015	$	55
	2016	29
	2017	19
	2018	11
	2019	7
	Thereafter	8
	Total future minimum lease payments	$	129
	We are a defendant in various lawsuits considered to be in the normal course of business. Members of our 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, we believe the outcome of pending litigation will not have a material adverse effect on our financial position, results of operations, or cash flows.

UNAUDITED_CONSOLIDATED_QUARTER

UNAUDITED CONSOLIDATED QUARTERLY FINANCIAL DATA	12 Months Ended
	Dec. 31, 2014
Disclosure Unaudited Consolidated Financial Quarterly Data [Abstract]
UNAUDITED CONSOLIDATED QUARTERLY FINANCIAL DATA	UNAUDITED CONSOLIDATED QUARTERLY FINANCIAL DATA
	In management's opinion, the following quarterly financial information fairly presents the results of operations for such periods and is prepared on a basis consistent with our annual audited financial statements.
	(In millions, except for per-share amounts)	March 31,				June 30,			September 30,			December 31,
		2014				2014			2014			2014
	Net premium income		$	4,854			$	4,888		$	4,841		$	4,489
	Net investment income		827				843			841			808
	Realized investment gains (losses)		(46		)		102			16			143
	Other income		5				5			38			74
	Total revenues		5,640				5,838			5,736			5,514
	Total benefits and expenses		4,536				4,600			4,662			4,439
	Earnings before income taxes		1,104				1,238			1,074			1,075
	Total income tax		372				428			368			372
	Net earnings		$	732			$	810		$	706		$	703
	Net earnings per basic share		$	1.61			$	1.79		$	1.56		$	1.57
	Net earnings per diluted share		1.6				1.78			1.56			1.57
	Quarterly amounts may not agree in total to the corresponding annual amounts due to rounding.
	(In millions, except for per-share amounts)	March 31,				June 30,			September 30,			December 31,
		2013				2013			2013			2013
	Net premium income		$	5,184			$	5,013		$	5,028		$	4,910
	Net investment income		833				813			821			826
	Realized investment gains (losses)		156				201			22			20
	Other income		35				17			15			45
	Total revenues		6,208				6,044			5,886			5,801
	Total benefits and expenses		4,847				4,686			4,817			4,773
	Earnings before income taxes		1,361				1,358			1,069			1,028
	Total income tax		469				469			367			353
	Net earnings		$	892			$	889		$	702		$	675
	Net earnings per basic share		$	1.91			$	1.91		$	1.51		$	1.46
	Net earnings per diluted share		1.9				1.9			1.5			1.45
	Quarterly amounts may not agree in total to the corresponding annual amounts due to rounding.

SCHEDULE_II_CONDENSED_FINANCIA

SCHEDULE II CONDENSED FINANCIAL INFORMATION OF REGISTRANT	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
SCHEDULE II CONDENSED FINANCIAL INFORMATION OF REGISTRANT	SCHEDULE II
	CONDENSED FINANCIAL INFORMATION OF REGISTRANT
	Aflac Incorporated (Parent Only)
	Condensed Statements of Earnings
		Years ended December 31,
	(In millions)	2014					2013					2012
	Revenues:
	Dividends from subsidiaries(1)		$	1,483				$	962				$	0
	Management and service fees from subsidiaries(1)		272					292					249
	Net investment income		13					11					20
	Interest from subsidiaries(1)		6					7					7
	Realized investment gains (losses)		45					10					1
	Change in fair value of the cross-currency interest rate swaps		314					274					154
	Other income (loss)		(11		)			1					(7		)
	Total revenues		2,122					1,557					424
	Operating expenses:
	Interest expense		243					208					184
	Other operating expenses		88					79					72
	Total operating expenses		331					287					256
	Earnings before income taxes and equity in undistributed earnings of		1,791					1,270					168
	subsidiaries
	Income tax expense (benefit):
	Current		1					0					1
	Deferred		120					98					50
	Total income taxes		121					98					51
	Earnings before equity in undistributed earnings of subsidiaries		1,670					1,172					117
	Equity in undistributed earnings of subsidiaries(1)		1,281					1,986					2,749
	Net earnings		$	2,951				$	3,158				$	2,866
	(1)Eliminated in consolidation
	See the accompanying Notes to Condensed Financial Statements.
	See the accompanying Report of Independent Registered Public Accounting Firm.
	SCHEDULE II
	CONDENSED FINANCIAL INFORMATION OF REGISTRANT
	Aflac Incorporated (Parent Only)
	Condensed Statements of Comprehensive Income (Loss)
		Years ended December 31,
	(In millions)	2014					2013					2012
	Net earnings		$	2,951				$	3,158				$	2,866
	Other comprehensive income (loss) before income taxes:
	Foreign currency translation adjustments:
	Unrealized foreign currency translation gains (losses)		39					48					95
	during period - parent only
	Equity in unrealized foreign currency translation gains (losses) of		(1,494		)			(1,636		)			(382		)
	subsidiaries during period
	Unrealized gains (losses) on investment securities:
	Unrealized holding gains (losses) on investment securities		9					(12		)			15
	during period - parent only
	Equity in unrealized holding gains (losses) on investment securities		5,938					(2,350		)			1,645
	held by subsidiaries during period
	Equity in reclassification adjustment for realized (gains) losses of		(54		)			(56		)			497
	subsidiaries included in net earnings
	Unrealized gains (losses) on derivatives during period		(17		)			(10		)			(22		)
	Pension liability adjustment during period		(76		)			157					(20		)
	Total other comprehensive income (loss) before		4,345					(3,859		)			1,828
	income taxes
	Income tax expense (benefit) related to items of other comprehensive		1,803					(581		)			1,078
	income (loss)
	Other comprehensive income (loss), net of income taxes		2,542					(3,278		)			750
	Total comprehensive income (loss)		$	5,493				$	(120	)			$	3,616
	See the accompanying Notes to Condensed Financial Statements.
	See the accompanying Report of Independent Registered Public Accounting Firm.
	SCHEDULE II
	CONDENSED FINANCIAL INFORMATION OF REGISTRANT
	Aflac Incorporated (Parent Only)
Condensed Balance Sheets
	December 31,
(In millions, except for share and per-share amounts)	2014					2013
Assets:
Investments and cash:
Fixed maturity securities available for sale, at fair value		$	437				$	332
(amortized cost $419 in 2014 and $322 in 2013)
Investments in subsidiaries(1)		21,430					17,678
Other investments		24					313
Cash and cash equivalents		1,638					1,081
Total investments and cash		23,529					19,404
Due from subsidiaries(1)		116					128
Other assets		766					464
Total assets		$	24,411				$	19,996
Liabilities and shareholders' equity:
Liabilities:
Income taxes		$	6				$	(120	)
Employee benefit plans		282					246
Notes payable		5,285					4,910
Other liabilities		491					340
Total liabilities		6,064					5,376
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in		67					67
2014 and 2013; issued 668,132 shares in 2014 and 667,046 shares in 2013
Additional paid-in capital		1,711					1,644
Retained earnings		22,156					19,885
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains		(2,541		)			(1,505		)
Unrealized gains (losses) on investment securities		4,672					1,035
Unrealized gains (losses) on derivatives		(26		)			(12		)
Pension liability adjustment		(126		)			(81		)
Treasury stock, at average cost		(7,566		)			(6,413		)
Total shareholders' equity		18,347					14,620
Total liabilities and shareholders' equity		$	24,411				$	19,996
(1)Eliminated in consolidation
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
SCHEDULE II
CONDENSED FINANCIAL INFORMATION OF REGISTRANT
Aflac Incorporated (Parent Only)
Condensed Statements of Cash Flows
	Years ended December 31,
(In millions)	2014					2013					2012
Cash flows from operating activities:
Net earnings		$	2,951				$	3,158				$	2,866
Adjustments to reconcile net earnings to net cash provided from
operating activities:
Equity in undistributed earnings of subsidiaries(1)		(1,281		)			(1,986		)			(2,749		)
Change in income tax liabilities		115					155					111
Other, net		(72		)			11					(242		)
Net cash provided (used) by operating activities		1,713					1,338					(14		)
Cash flows from investing activities:
Fixed maturity securities sold		38					8					13
Fixed maturity securities purchased		(105		)			(206		)			(26		)
Other investments sold (purchased)		290					(298		)			(3		)
Net cash provided (used) by investing activities		223					(496		)			(16		)
Cash flows from financing activities:
Purchases of treasury stock		(1,210		)			(813		)			(118		)
Proceeds from borrowings		750					700					1,506
Principal payments under debt obligations		(335		)			0					(380		)
Dividends paid to shareholders		(654		)			(635		)			(603		)
Treasury stock reissued		33					88					70
Proceeds from exercise of stock options		23					41					21
Net change in amount due to/from subsidiaries(1)		14					28					(21		)
Net cash provided (used) by financing activities		(1,379		)			(591		)			475
Net change in cash and cash equivalents		557					251					445
Cash and cash equivalents, beginning of period		1,081					830					385
Cash and cash equivalents, end of period		$	1,638				$	1,081				$	830
(1)Eliminated in consolidation
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
(A) Notes Payable
A summary of notes payable as of December 31 follows:
(In millions)	2014					2013
3.45% senior notes due August 2015		$	300				$	300
2.65% senior notes due February 2017		653			(1)		655			(1)
8.50% senior notes due May 2019		850					850
4.00% senior notes due February 2022		350			(2)		349			(2)
3.625% senior notes due June 2023		700					700
3.625% senior notes due November 2024		749					0
6.90% senior notes due December 2039		397			(2)		396			(2)
6.45% senior notes due August 2040		448			(2)		448			(2)
5.50% subordinated debentures due September 2052		500					500
Yen-denominated Uridashi notes:
2.26% notes due September 2016 (principal amount 10 billion yen)		83					95
Yen-denominated Samurai notes:
1.47% notes paid July 2014 (principal amount 28.7 billion yen)		0					272
1.84% notes due July 2016 (principal amount 15.8 billion yen)		131					150
Variable interest rate notes paid July 2014 (1.30% in 2013, principal amount		0					52
5.5 billion yen)
Yen-denominated loans:
3.60% loan due July 2015 (principal amount 10 billion yen)		83					95
3.00% loan due August 2015 (principal amount 5 billion yen)		41					48
Total notes payable		$	5,285				$	4,910
(1) Principal amount plus an issuance premium that is being amortized over the life of the notes
(2) Principal amount net of an issuance discount that is being amortized over the life of the notes
During 2009, Aflac Japan bought on the open market 2.0 billion yen of yen-denominated Uridashi notes issued by the Parent Company which are outstanding as of December 31, 2014. In consolidation, those notes have been extinguished; however, they remain an outstanding liability for the Parent Company until their maturity date.
The aggregate contractual maturities of notes payable during each of the years after December 31, 2014, are as follows:
(In millions)
2015	$	424
2016	214
2017	650
2018	0
2019	850
Thereafter	3,150
Total	$	5,288
For further information regarding notes payable, see Note 9 of the Notes to the Consolidated Financial Statements.
(B) Derivatives
At December 31, 2014, the Parent Company's outstanding freestanding derivative contracts were swaps associated with our notes payable, consisting of cross-currency interest rate swaps, also referred to as foreign currency swaps, associated with our senior notes due in February 2017, February 2022, June 2023 and November 2024, and subordinated debentures due in September 2052. We do not use derivative financial instruments for trading purposes, nor do we engage in leveraged derivative transactions. For further information regarding these derivatives, see Notes 1, 4 and 9 of the Notes to the Consolidated Financial Statements.
(C) Income Taxes
The Parent Company and its eligible U.S. subsidiaries file a consolidated U.S. federal income tax return. Income tax liabilities or benefits are recorded by each principal subsidiary based upon separate return calculations, and any difference between the consolidated provision and the aggregate amounts recorded by the subsidiaries is reflected in the Parent Company financial statements. For further information on income taxes, see Note 10 of the Notes to the Consolidated Financial Statements.
(D) Dividend Restrictions
See Note 13 of the Notes to the Consolidated Financial Statements for information regarding dividend restrictions.
(E) Supplemental Disclosures of Cash Flow Information
(In millions)	2014					2013					2012
Interest paid		$	241				$	205				$	181
Noncash financing activities:
Treasury stock issued for shareholder dividend reinvestment		26					25					25

SCHEDULE_III_SUPPLEMENTARY_INS

SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION	12 Months Ended
	Dec. 31, 2014
Supplementary Insurance Information [Abstract]
SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION	SCHEDULE III
	SUPPLEMENTARY INSURANCE INFORMATION
	Aflac Incorporated and Subsidiaries
	Years ended December 31,
	(In millions)	Deferred Policy					Future Policy					Unearned					Other
		Acquisition					Benefits & Unpaid					Premiums					Policyholders'
		Costs					Policy Claims										Funds
	2014:00:00
	Aflac Japan		$	5,211				$	60,036				$	8,509				$	6,030
	Aflac U.S.		3,062					9,239					117					0
	All other		0					1					0					1
	Total		$	8,273				$	69,276				$	8,626				$	6,031
	2013:00:00
	Aflac Japan		$	5,819				$	64,122				$	10,520				$	5,660
	Aflac U.S.		2,979					8,775					122					201
	All other		0					2					0					0
	Total		$	8,798				$	72,899				$	10,642				$	5,861
	Segment amounts may not agree in total to the corresponding consolidated amounts due to rounding.
	Years Ended December 31,
	(In millions)	Net			Net					Benefits and					Amortization of					Other			Premiums
		Premium			Investment					Claims, net					Deferred Policy					Operating			Written
		Revenue			Income										Acquisition Costs					Expenses
	2014:00:00
	Aflac Japan	$	13,861			$	2,662				$	10,084				$	649				$	2,364	$	13,352
	Aflac U.S.	5,211				645					2,853					459					1,474		5,198
	All other	0				12					0					0					354		0
	Total	$	19,072			$	3,319				$	12,937				$	1,108				$	4,192	$	18,550
	2013:00:00
	Aflac Japan	$	14,982			$	2,651				$	10,924				$	641				$	2,495	$	15,960
	Aflac U.S.	5,153				632					2,889					433					1,431		5,144
	All other	0				10					0					0					310		0
	Total	$	20,135			$	3,293				$	13,813				$	1,074				$	4,236	$	21,104
	2012:00:00
	Aflac Japan	$	17,151			$	2,845				$	12,496				$	716				$	2,937	$	23,662
	Aflac U.S.	4,996				613					2,834					400					1,397		4,988
	All other	1				15					0					1					281		0
	Total	$	22,148			$	3,473				$	15,330				$	1,117				$	4,615	$	28,650
	Segment amounts may not agree in total to the corresponding consolidated amounts due to rounding.
	See the accompanying Report of Independent Registered Public Accounting Firm.

SCHEDULE_IV_REINSURANCE

SCHEDULE IV REINSURANCE	12 Months Ended
	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
SCHEDULE IV REINSURANCE	SCHEDULE IV
	REINSURANCE
	Aflac Incorporated and Subsidiaries
	Years Ended December 31,
	(In millions)	Gross		Ceded to			Assumed			Net		Percentage
		Amount		Other			from Other			Amount		of Amount
				Companies			companies					Assumed
												to Net
	2014:00:00
	Life insurance in force	$	144,374		$	3,298		$	0	$	141,076		0	%
	Premiums:
	Health insurance	$	14,648		$	339		$	10	$	14,319		0	%
	Life insurance	4,764			11			0		4,753			0
	Total earned premiums	$	19,412		$	350		$	10	$	19,072		0	%
	2013:00:00
	Life insurance in force	$	157,022		$	3,245		$	0	$	153,777		0	%
	Premiums:
	Health insurance	$	15,393		$	98		$	12	$	15,307		0	%
	Life insurance	4,840			12			0		4,828			0
	Total earned premiums	$	20,233		$	110		$	12	$	20,135		0	%
	2012:00:00
	Life insurance in force	$	173,791		$	3,867		$	0	$	169,924		0	%
	Premiums:
	Health insurance	$	17,541		$	19		$	14	$	17,536		0	%
	Life insurance	4,626			14			0		4,612			0
	Total earned premiums	$	22,167		$	33		$	14	$	22,148		0	%
	Premiums by type may not agree in total to the corresponding consolidated amounts due to rounding.
	See the accompanying Report of Independent Registered Public Accounting Firm.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2014
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 and Japan. The Company's insurance business is marketed and administered through American Family Life Assurance Company of Columbus (Aflac), which operates in the United States (Aflac U.S.) and as a branch in Japan (Aflac Japan). American Family Life Assurance Company of New York (Aflac New York) is a wholly owned subsidiary of Aflac. Most of Aflac's policies are individually underwritten and marketed through independent agents. Additionally, Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. Our insurance operations in the United States and our branch in Japan service the two markets for our insurance business. Aflac Japan's revenues, including realized gains and losses on its investment portfolio, accounted for 72% of the Company's total revenues in 2014, compared with 74% in 2013 and 77% in 2012. The percentage of the Company's total assets attributable to Aflac Japan was 82% at December 31, 2014, compared with 85% at December 31, 2013.
	Basis of Presentation
	We prepare our financial statements in accordance with U.S. generally accepted accounting principles (GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to GAAP issued by the FASB are derived from the FASB Accounting Standards CodificationTM (ASC). The preparation of financial statements in conformity with GAAP requires us to make estimates when recording transactions resulting from business operations based on currently available information. The most significant items on our balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments, deferred policy acquisition costs, 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, we believe the amounts provided are adequate.
	The 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.
Translation of Foreign Currencies	Translation of Foreign Currencies: The functional currency of Aflac Japan's insurance operations is the Japanese yen. We translate our yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. We include in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.
	Prior to October 1, 2013, Aflac Japan maintained an investment portfolio of dollar-denominated securities on behalf of Aflac U.S., which served as an economic currency hedge of a portion of our investment in Aflac Japan. The functional currency for these investments was the U.S. dollar. The related investment income and realized/unrealized investment gains and losses were denominated in U.S. dollars. Since the functional currency of this portfolio was the U.S. dollar, there was no translation adjustment to record in other comprehensive income for these investments when the yen/dollar exchange rate changed. The foreign exchange gains and losses related to this portfolio continue to be taxable in Japan and the U.S. when the securities matured or were sold. Until maturity or sale, deferred tax expense or benefit associated with the foreign exchange gains or losses is recognized in income tax expense on other comprehensive income. As of October 1, 2013, these investments were transferred into the Aflac Japan investment portfolio. These investments began to have remeasurement and translation effects recorded in other comprehensive income in the fourth quarter of 2013.
	We have designated a majority of the Parent Company's yen-denominated liabilities (Samurai and Uridashi notes and yen-denominated loans) as non-derivative hedges and designated foreign currency forwards and options as derivative hedges of the foreign currency exposure of our investment in Aflac Japan. Outstanding principal and related accrued interest on these Parent Company liabilities and the fair value of these derivatives are translated into U.S. dollars at end-of-period exchange rates. Currency translation adjustments and changes in the fair value of these derivatives are recorded as unrealized foreign currency translation gains (losses) in other comprehensive income and are included in accumulated other comprehensive income.
Insurance Revenue and Expense Recognition	Insurance Revenue and Expense Recognition: The supplemental health and life insurance policies we issue are classified as long-duration contracts. The contract provisions generally cannot be changed or canceled during the contract period; however, we may adjust premiums for supplemental health policies issued in the United States within prescribed guidelines and with the approval of state insurance regulatory authorities.
	Insurance premiums for most of the Company's health and life policies are recognized ratably as earned income over the premium payment periods of the policies. When revenues are reported, the related amounts of benefits and expenses are charged against such revenues, so that profits are recognized in proportion to premium revenues during the period the policies are expected to remain in force. This association is accomplished by means of annual additions to the liability for future policy benefits and the deferral and subsequent amortization of policy acquisition costs.
	Premiums from the Company's products with limited-pay features are collected over a significantly shorter period than the period over which benefits are provided. Premiums for these products are recognized ratably over the scheduled premium payment period. At the policyholder's option, customers can also pay discounted advanced premiums for certain of these products. Advanced premiums are deferred and recognized ratably over the regularly scheduled premium payment period. For the Company's limited-pay products, any gross premium in excess of the net premium is deferred during the scheduled premium payment period and recognized into benefits in a constant relationship with insurance in force. Benefits are recorded as an expense when they are incurred. A liability for future policy benefits is recorded when premiums are recognized using the net premium method.
	The calculation of deferred policy acquisition costs (DAC) and the liability for future policy benefits requires the use of estimates based on sound actuarial valuation techniques. For new policy issues, we review our actuarial assumptions and deferrable acquisition costs each year and revise them when necessary to more closely reflect recent experience and studies of actual acquisition costs. For policies in force, we evaluate DAC by major product groupings to determine that they are recoverable from future revenues, and any amounts determined not to be recoverable are charged against net earnings. We have not had any material charges to earnings for DAC that was determined not to be recoverable in any of the years presented in this Form 10-K.
	Advertising expense is reported as incurred in insurance expenses in the consolidated statements of earnings.
Cash and Cash Equivalents	Cash and Cash Equivalents: Cash and cash equivalents include cash on hand, money market instruments and other debt instruments with a maturity of 90 days or less when purchased.
Investments	Investments: Our debt securities consist of fixed-maturity securities, which are classified as either held to maturity or available for sale. Securities classified as held to maturity are securities that we have the ability and intent to hold to maturity or redemption and are carried at amortized cost. All other fixed-maturity debt securities, our perpetual securities and our equity securities are classified as available for sale and are carried at fair value. If the fair value is higher than the amortized cost for debt and perpetual securities, or the purchase cost for equity securities, the excess is an unrealized gain, and if lower than cost, the difference is an unrealized loss. The net unrealized gains and losses on securities available for sale, plus the unamortized unrealized gains and losses on debt securities transferred to the held-to-maturity portfolio, less related deferred income taxes, are recorded through other comprehensive income and included in accumulated other comprehensive income.
	Amortized cost of debt and perpetual securities is based on our purchase price adjusted for accrual of discount, or amortization of premium, and recognition of impairment charges, if any. The amortized cost of debt and perpetual securities we purchase at a discount or premium will equal the face or par value at maturity or the call date, if applicable. Interest is reported as income when earned and is adjusted for amortization of any premium or discount.
	We have investments in variable interest entities (VIEs). Criteria for evaluating VIEs for consolidation focuses on identifying which enterprise has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. We are the primary beneficiary of certain VIEs. While the VIEs generally operate within a defined set of documents, there are certain powers that are retained by us that are considered significant in our conclusion that we are the primary beneficiary. These powers vary by structure but generally include the initial selection of the underlying collateral or, for collateralized debt obligations (CDOs), the reference credits to include in the structure; the ability to obtain the underlying collateral in the event of default; and the ability to appoint or dismiss key parties in the structure. In particular, our powers surrounding the underlying collateral were the most significant powers since those most significantly impact the economics of the VIE. We have no obligation to provide any continuing financial support to any of the entities in which we are the primary beneficiary. Our maximum loss is limited to our original investment. Neither we nor any of our creditors have the ability to obtain the underlying collateral, nor do we have control over the instruments in the VIEs, unless there is an event of default. For those entities where we are the primary beneficiary, the assets consolidated are fixed-maturity securities, perpetual securities and derivative instruments; collateral is reported separately under the captions fixed maturities- and perpetual securities- consolidated variable interest entities on our balance sheet.
	For the collateralized mortgage obligations (CMOs) held in our fixed-maturity securities portfolio, we recognize income using a constant effective yield, which is based on anticipated prepayments and the estimated economic life of the securities. When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The net investment in CMO securities is adjusted to the amount that would have existed had the new effective yield been applied at the time of acquisition. This adjustment is reflected in net investment income.
	We use the specific identification method to determine the gain or loss from securities transactions and report the realized gain or loss in the consolidated statements of earnings. Securities transactions are accounted for based on values as of the trade date of the transaction.
	An investment in a fixed maturity or perpetual security is impaired if the fair value falls below book value. We regularly review our entire investment portfolio for declines in value. The majority of our investments are evaluated for other-than-temporary impairment using our debt impairment model. Our debt impairment model focuses on the ultimate collection of the cash flows from our investments. The determination of the amount of impairments under this model is based upon our periodic evaluation and assessment of known and inherent risks associated with the respective securities. Such evaluations and assessments are revised as conditions change and new information becomes available.
	The determination of whether an impairment in value is other than temporary is based largely on our evaluation of the issuer's creditworthiness. Our team of experienced credit professionals must apply considerable judgment in determining the likelihood of the security recovering in value while we own it. Factors that may influence this include the overall level of interest rates, credit spreads, the credit quality of the underlying issuer, and other factors. This process requires consideration of risks which can be controlled to a certain extent, such as credit risk, and risks which cannot be controlled, such as interest rate risk.
	If, after monitoring and analyses, management believes that fair value will not recover to amortized cost prior to the disposal of the security, we recognize an other-than-temporary impairment of the security. Once a security is considered to be other-than-temporarily impaired, the impairment loss is separated into two separate components: the portion of the impairment related to credit and the portion of the impairment related to factors other than credit. We automatically recognize a charge to earnings for the credit-related portion of other-than-temporary impairments. Impairments related to factors other than credit are charged to earnings in the event we intend to sell the security prior to the recovery of its amortized cost or if it is more likely than not that we would be required to dispose of the security prior to recovery of its amortized cost; otherwise, non-credit-related other-than-temporary impairments are charged to other comprehensive income.
	Our investments in perpetual securities that are rated below investment grade are evaluated for other-than-temporary impairment under our equity impairment model. Our equity impairment model focuses on the severity of a security's decline in fair value coupled with the length of time the fair value of the security has been below amortized cost and the financial condition and near-term prospects of the issuer.
	We lend fixed-maturity securities to financial institutions in short-term security lending transactions. These securities continue to be carried as investment assets on our balance sheet during the terms of the loans and are not reported as sales. We receive cash or other securities as collateral for such loans. For loans involving unrestricted cash or securities as collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral.
	Other investments include policy loans and other short-term investments with maturities of one year or less, but greater than 90 days, at the time of purchase and are stated at amortized cost, which approximates estimated fair value.
Derivatives and Hedging	Derivatives and Hedging: Freestanding derivative instruments are reported in the consolidated balance sheet at fair value and are reported in other assets and other liabilities, with changes in value reported in earnings and/or other comprehensive income. These freestanding derivatives are interest rate swaps, foreign currency swaps, credit default swaps (CDSs), foreign currency forwards, foreign currency options, and options on interest rate swaps (or interest rate swaptions). Interest rate and foreign currency swaps are used within VIEs to hedge the risk arising from interest rate and currency exchange risk, while the CDSs are used to increase the yield and improve the diversification of the portfolio. Foreign currency forwards and options are used in hedging foreign exchange risk on U.S. dollar-denominated securities in Aflac Japan's portfolio. Foreign currency forwards and options are used to hedge certain portions of forecasted cash flows denominated in yen. Interest rate swaps are used to hedge the variability of interest cash flows associated with our variable interest rate notes, and cross-currency interest rate swaps, also referred to as foreign currency swaps, are used to economically convert certain dollar-denominated note obligations into yen-denominated principal and interest obligations. Interest rate swaptions are used to hedge interest rate risk for certain U.S. dollar-denominated available-for-sale securities. We do not use derivatives for trading purposes, nor do we engage in leveraged derivative transactions.
	From time to time, we purchase certain investments that contain an embedded derivative. We assess whether this embedded derivative is clearly and closely related to the asset that serves as its host contract. If we deem that the embedded derivative's terms are not clearly and closely related to the host contract, and a separate instrument with the same terms would qualify as a derivative instrument, the derivative is separated from that contract, held at fair value and reported with the host instrument in the consolidated balance sheet, with changes in fair value reported in earnings. If we have elected the fair value option, the embedded derivative is not bifurcated, and the entire investment is held at fair value with changes in fair value reported in earnings.
	For those relationships where we seek hedge accounting, we formally document all relationships between hedging instruments and hedged items, as well as our risk-management objectives and strategies for undertaking various hedge transactions. This process includes linking derivatives and nonderivatives that are designated as hedges to specific assets or liabilities on the balance sheet. We also assess, both at inception and on an ongoing basis, whether the derivatives and nonderivatives used in hedging activities are highly effective in offsetting changes in fair values or cash flows of the hedged items. The assessment of hedge effectiveness determines the accounting treatment of noncash changes in fair value.
	Changes in the fair value of any of our derivatives that are designated and qualify as cash flow hedges are recorded in other comprehensive income as long as they are deemed effective. Any hedge ineffectiveness is recorded immediately in current period earnings within derivative and other gains (losses). Periodic derivative net coupon settlements are recorded in the line item of the consolidated statements of earnings in which the cash flows of the hedged item are recorded.
	Changes in the estimated fair value of derivative instruments that are designated and qualify as fair value hedges, including amounts measured as ineffectiveness, and changes in the estimated fair value of the hedged item related to the designated risk being hedged, are reported in current earnings within derivative and other gains (losses).
	We have designated the majority of the Parent Company's yen-denominated liabilities (Samurai and Uridashi notes and yen-denominated loans) as nonderivative hedges and designated derivatives as hedges of the foreign currency exposure to our investment in Aflac Japan. At the beginning of each quarter, we make our net investment hedge designation. If the total of the designated Parent Company non-derivative and derivatives notional is equal to or less than our net investment in Aflac Japan, the hedge is deemed to be effective, and the exchange effect on the yen-denominated liabilities and the change in estimated fair value of the derivatives are reported in the unrealized foreign currency component of other comprehensive income. Should these designated net investment hedge positions exceed our net investment in Aflac Japan, the foreign exchange effect on the portion that exceeds our investment in Aflac Japan would be recognized in current earnings within derivative and other gains (losses).
	Derivatives that are not designated as hedges are carried at fair value with all changes in fair value recorded in current period earnings within derivative and other gains (losses). We include the fair value of all freestanding derivatives in either other assets or other liabilities on the balance sheet.
	We receive and pledge cash or other securities as collateral on open derivative positions. Cash received as collateral is reported as an asset with a corresponding liability for the return of the collateral. Cash pledged as collateral is recorded as a reduction to cash, and a corresponding receivable is recognized for the return of the cash collateral. We generally can repledge or resell collateral obtained by us, although we do not typically exercise such rights. Securities received as collateral are not recognized unless we were to exercise our right to sell that collateral or exercise remedies on that collateral upon a counterparty default. Securities that we have pledged as collateral continue to be carried as investment assets on our balance sheet.
Deferred Policy Acquisition Costs	Deferred Policy Acquisition Costs: Certain direct and incremental costs of acquiring new business are deferred and amortized with interest over the premium payment periods in proportion to the ratio of annual premium income to total anticipated premium income. Anticipated premium income is estimated by using the same mortality, persistency and interest assumptions used in computing liabilities for future policy benefits. In this manner, the related acquisition expenses are matched with revenues. Deferred costs include the excess of current-year commissions over ultimate renewal-year commissions and certain incremental direct policy issue, underwriting and sales expenses. All of these incremental costs are directly related to successful policy acquisition.
	For some products, policyholders can elect to modify product benefits, features, rights or coverages by exchanging a contract for a new contract or by amendment, endorsement, or rider to a contract, or by the election of a feature or coverage within a contract. These transactions are known as internal replacements. For internal replacement transactions where the resulting contract is substantially unchanged, the policy is accounted for as a continuation of the replaced contract. Unamortized deferred acquisition costs from the original policy continue to be amortized over the expected life of the new policy, and the costs of replacing the policy are accounted for as policy maintenance costs and expensed as incurred. Internal replacement transactions that result in a policy that is not substantially unchanged are accounted for as an extinguishment of the original policy and the issuance of a new policy. Unamortized deferred acquisition costs on the original policy that was replaced are immediately expensed, and the costs of acquiring the new policy are capitalized and amortized in accordance with our accounting policies for deferred acquisition costs.
	We measure the recoverability of DAC and the adequacy of our policy reserves annually by performing gross premium valuations on our business. Our testing indicates that our DAC is recoverable and our policy liabilities are adequate. (See the following discussion for further information regarding policy liabilities.)
Policy Liabilities - Future Policy Benefits	Policy Liabilities: Future policy benefits represent claims that are expected to occur in the future and are computed by a net level premium method using estimated future investment yields, persistency and recognized morbidity and mortality tables modified to reflect our experience, including a provision for adverse deviation. These assumptions are generally established at the time a policy is issued.
Policy Liabilities - Unpaid Policy Claims	Unpaid policy claims are estimates computed on an undiscounted basis using statistical analyses of historical claims experience adjusted for current trends and changed conditions. The ultimate liability may vary significantly from such estimates. We regularly adjust these estimates as new claims experience emerges and reflect the changes in operating results in the year such adjustments are made.
Other Policy Liabilities	Other policy liabilities consist primarily of discounted advance premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as premium revenue over the contractual premium payment period.
Internal Replacements of Insurance Contracts	For internal replacements that are determined to not be substantially unchanged, policy liabilities related to the original policy that was replaced are immediately released, and policy liabilities are established for the new insurance contract.
Reinsurance Accounting Policy	Reinsurance: We enter into reinsurance agreements with other companies in the normal course of business. For each of our reinsurance agreements, we determine if 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, benefits and DAC are reported net of insurance ceded. See Note 8 of the Notes to the Consolidated Financial Statements for additional information.
Income Taxes	Income Taxes: Income tax provisions are generally based on pretax earnings reported for financial statement purposes, which differ from those amounts used in preparing our income tax returns. Deferred income taxes are recognized for temporary differences between the financial reporting basis and income tax basis of assets and liabilities, based on enacted tax laws and statutory tax rates applicable to the periods in which we expect the temporary differences to reverse. We record deferred tax assets for tax positions taken based on our assessment of whether the tax position is more likely than not to be sustained upon examination by taxing authorities. A valuation allowance is established for deferred tax assets when it is more likely than not that an amount will not be realized.
	As discussed in the Translation of Foreign Currencies section above, Aflac Japan maintains certain dollar-denominated investments that, prior to October 1, 2013, did not have any foreign currency translation adjustments recognized in other comprehensive income. However, the deferred tax expense or benefit associated with foreign exchange gains or losses on these investments is recognized in other comprehensive income (loss) until the securities mature or are sold. Total income tax expense (benefit) related to items of other comprehensive income (loss) included a deferred tax expense of $614 million in 2013 and $492 million in 2012 for these dollar-denominated investments. Excluding these amounts from total taxes on other comprehensive income would result in an effective income tax rate on pretax other comprehensive income (loss) of 31% in 2013 and 32% in 2012.
Policyholder Protection Corporation and State Guaranty Association Assessments	Policyholder Protection Corporation and State Guaranty Association Assessments: In Japan, the government has required the insurance industry to contribute to a policyholder protection corporation. We recognize a charge for our estimated share of the industry's obligation once it is determinable. We review the estimated liability for policyholder protection corporation contributions on an annual basis and report any adjustments in Aflac Japan's expenses.
	In the United States, each state has a guaranty association that supports insolvent insurers operating in those states. To date, our state guaranty association assessments have not been material.
Treasury Stock	Treasury Stock: Treasury stock is reflected as a reduction of shareholders' equity at cost. We use the weighted-average purchase cost to determine the cost of treasury stock that is reissued. We include any gains and losses in additional paid-in capital when treasury stock is reissued.
Share-Based Compensation	Share-Based Compensation: We measure compensation cost related to our share-based payment transactions at fair value on the grant date, and we recognize those costs in the financial statements over the vesting period during which the employee provides service in exchange for the award.
Earnings Per Share	Earnings Per Share: We compute basic earnings per share (EPS) by dividing net earnings by the weighted-average number of unrestricted shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the weighted-average number of shares outstanding for the period plus the shares representing the dilutive effect of share-based awards.
Reclassifications	Reclassifications: Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. Components of our deferred inventory were reclassified to separately reflect deferred foreign currency gains and losses which were previously apportioned to each component of the deferred inventory, see Note 10 of the Notes to the Consolidated Financial Statements. These reclassifications had no impact on net earnings or total shareholders' equity.
Recently Adopted Accounting Pronouncements	New Accounting Pronouncements
	Recently Adopted Accounting Pronouncements
	Presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists: In July 2013, the FASB issued guidance to amend the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The new guidance essentially states that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. However, to the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. This accounting standard applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists at the reporting date. This guidance is effective for annual reporting periods beginning on or after December 15, 2013, and interim periods within those annual periods and requires prospective presentation for all comparative periods presented. We adopted this guidance as of January 1, 2014. The adoption of this guidance did not have a significant impact on our financial statements.
	Derivatives and hedging: In July 2013, the FASB issued an update which allows entities to use the Federal Funds Effective Swap Rate, also referred to as the Overnight Index Swap Rate (OIS), as a benchmark interest rate for hedge accounting purposes. Previously the only acceptable benchmark rates for hedge accounting purposes under GAAP were U.S. Treasury rates and the London Interbank Offered Rate (LIBOR) swap rate. This update reflects the evolution of market hedging practices and is intended to provide more flexibility for hedge accounting purposes. We adopted this guidance in the third quarter of 2013 on a prospective basis for qualifying new or redesignated hedging relationships entered into on or after the effective date of July 17, 2013. The adoption of the guidance had no impact on our financial position or results of operations.
	Reporting of amounts reclassified out of accumulated other comprehensive income: In February 2013, the FASB issued guidance that requires reclassification adjustments for items that are reclassified out of accumulated other comprehensive income to net income to be presented in statements where the components of net income and the components of other comprehensive income are presented or in the footnotes to the financial statements. Additionally, the amendment requires cross-referencing to other disclosures currently required for other reclassification items. We adopted this guidance as of January 1, 2013. The adoption of this guidance impacted our financial statement disclosures, but it did not have an impact on our financial position or results of operations.
	Disclosures about offsetting assets and liabilities: In December 2011, the FASB issued guidance to amend the disclosure requirements about offsetting assets and liabilities. The new guidance essentially clarifies the FASB's intent concerning the application of existing offsetting disclosure requirements. Entities are required to disclose gross and net information about both instruments and transactions eligible for offset in the statement of financial position and instruments and transactions when those activities are subject to an agreement similar to a master netting arrangement. The scope of this guidance was clarified and revised in January 2013 to apply to derivatives, repurchase agreements, reverse repurchase agreements, securities borrowing and securities lending arrangements. The objective of this disclosure is to move toward consistency between U.S. GAAP and International Financial Reporting Standards (IFRS). We adopted this guidance as of January 1, 2013. The adoption of this guidance impacted our financial statement disclosures, but it did not have an impact on our financial position or results of operations.
	Fees paid to the federal government by health insurers: In July 2011, the FASB issued guidance on the accounting for fees owed by health insurers as mandated by the Patient Protection and Affordable Care Act as amended by the Health Care and Education Reconciliation Act (the Acts). The Acts impose an annual fee on health insurers for each calendar year beginning on or after January 1, 2014. A health insurer's portion of the annual fee is payable by September 30 of the applicable calendar year once the entity provides health insurance for any U.S. health risk in that year. The annual fee for the health insurance industry will be allocated to individual health insurers based on the ratio of the amount of an entity's net premiums written during the preceding calendar year to the amount of health insurance for any U.S. health risk that is written during the preceding calendar year. The accounting guidance specifies that the liability for the fee should be estimated and recorded in full in the applicable calendar year in which the fee is payable with a corresponding deferred cost that is amortized to expense using a straight-line method of allocation unless another method better allocates the fee over the calendar year that it is payable. This guidance is effective for calendar years beginning after December 31, 2013. We adopted this guidance as of January 1, 2014. The adoption of this guidance did not have a significant impact on our financial position or results of operations.
	Presentation of comprehensive income: In June 2011, the FASB issued guidance to amend the presentation of comprehensive income. The amendment requires that all non-owner changes in shareholders' equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. We adopted this guidance as of January 1, 2012 and elected the option to report comprehensive income in two separate but consecutive statements. The adoption of this guidance did not have an impact on our financial position or results of operations.
	Fair value measurements and disclosures: In May 2011, the FASB issued guidance to amend the fair value measurement and disclosure requirements. Most of the amendments are clarifications of the FASB's intent about the application of existing fair value measurement and disclosure requirements. Other amendments change a particular principle or requirement for measuring fair value or disclosing information about fair value measurements. The new fair value measurement disclosures include additional quantitative and qualitative disclosures for Level 3 measurements, including a qualitative sensitivity analysis of fair value to changes in unobservable inputs, and categorization by fair value hierarchy level for items for which the fair value is only disclosed. We adopted this guidance as of January 1, 2012. The adoption of this guidance impacted our financial statement disclosures, but it did not affect our financial position or results of operations.
	Accounting for costs associated with acquiring or renewing insurance contracts: In October 2010, the FASB issued amended accounting guidance on accounting for costs associated with acquiring or renewing insurance contracts. Under the previous guidance, costs that varied with and were primarily related to the acquisition of a policy were deferrable. Under the amended guidance, only incremental direct costs associated with the successful acquisition of a new or renewal contract may be capitalized, and direct-response advertising costs may be capitalized only if they meet certain criteria. This guidance is effective on a prospective or retrospective basis for interim and annual periods beginning after December 15, 2011. We retrospectively adopted this guidance as of January 1, 2012. The retrospective adoption of this accounting standard resulted in an after-tax cumulative reduction to retained earnings of $391 million and an after-tax cumulative reduction to unrealized foreign currency translation gains in accumulated other comprehensive income of $67 million, resulting in a total reduction to shareholders' equity of $458 million as of December 31, 2009, the opening balance sheet date in the period of adoption. The adoption of this accounting standard had an immaterial impact on net income in 2011 and all preceding years.
Description of Accounting Pronouncements Pending Adoption	Accounting Pronouncements Pending Adoption
	Derivatives and Hedging - Determining whether the host contract in a hybrid financial instrument issued in the form of a share is more akin to debt or equity: In November 2014, the FASB issued guidance to clarify how to evaluate the economic characteristics and risks of a host contract in a hybrid financial instrument that is issued in the form of a share. The guidance also clarifies that an entity should assess the substance of the relevant terms and features when considering how to weight those terms and features. The guidance is effective for annual periods and interim periods beginning after December 15, 2015. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Presentation of Financial Statements - Going Concern - Disclosure of uncertainties about an entity’s ability to continue as a going concern: In August 2014, the FASB issued this amendment that provides U.S. GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. The amendment is effective for annual periods ending after December 15, 2016, and interim periods within annual periods beginning after December 15, 2016. Early application is permitted for annual or interim reporting periods for which the financial statements have not previously been issued. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Receivables - Troubled debt restructurings by creditors - classification of certain government-guaranteed mortgage loans upon foreclosure: In August 2014, the FASB issued updated guidance for troubled debt restructurings affecting creditors that hold government-guaranteed mortgage loans, including those guaranteed by the FHA and the VA. The guidance requires that a mortgage loan be derecognized and a separate other receivable be recognized upon foreclosure if certain conditions are met. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Compensation - Stock Compensation - Accounting for share-based payments when the terms of an award provide that a performance target could be achieved after the requisite service period: In June 2014, the FASB issued this amendment that provides guidance on certain share-based payment awards that require a specific performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. A reporting entity should apply existing guidance to awards with performance conditions that affect vesting to account for such awards. The performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. The guidance is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. Early adoption is permitted. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Transfers and Servicing, Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures: In June 2014, the FASB issued updated guidance for repurchase agreement and security lending transactions to change the accounting for repurchase-to-maturity transactions and linked repurchase financings to be accounted for as secured borrowings, consistent with the accounting for other repurchase agreements. The amendments also require new disclosures to increase transparency about the types of collateral pledged in repurchase agreements and similar transactions accounted for as secured borrowings. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Revenue from contracts with customers: In May 2014, the FASB issued updated guidance that affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (e.g., insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The amendments are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. The adoption of this guidance will not have a significant impact on our financial position or results of operations.
	Receivables - Troubled debt restructurings by creditors - Reclassification of residential real estate collateralized consumer mortgage loans upon foreclosure: In January 2014, the FASB issued updated guidance for troubled debt restructurings clarifying when an in substance repossession or foreclosure occurs, and when a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan. The new guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The adoption of this guidance will not have a significant impact on our financial position or results of operations.

BUSINESS_SEGMENT_AND_FOREIGN_I1

BUSINESS SEGMENT AND FOREIGN INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Reconciliation of Revenue from Segments to Consolidated	Information regarding operations by segment for the years ended December 31 follows:
	(In millions)	2014					2013					2012
	Revenues:
	Aflac Japan:
	Net earned premiums:
	Cancer		$	5,596				$	6,123				$	7,537
	Medical and other health		3,770					4,282					5,244
	Life insurance		4,495					4,577					4,370
	Net investment income		2,662					2,651					2,845
	Other income		32					55					57
	Total Aflac Japan		16,555					17,688					20,053
	Aflac U.S.:
	Earned premiums:
	Accident/disability		2,303					2,284					2,213
	Cancer		1,279					1,283					1,282
	Other health		1,371					1,334					1,259
	Life insurance		258					252					242
	Net investment income		645					632					613
	Other income		3					6					19
	Total Aflac U.S.		5,859					5,791					5,628
	Other business segments		43					49					46
	Total business segment revenues		22,457					23,528					25,727
	Realized investment gains (losses)		171			(1)		389			(1)		(349		)
	Corporate		281					302					269
	Intercompany eliminations		(248		)			(308		)			(276		)
	Other non-operating income (loss)		67					28					(7		)
	Total revenues		$	22,728				$	23,939				$	25,364
	(1) Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
	(In millions)	2014					2013					2012
	Pretax earnings:
	Aflac Japan		$	3,458				$	3,628				$	3,904
	Aflac U.S.		1,073					1,038					997
	Other business segments		(2		)			(1		)			(3		)
	Total business segment pretax operating earnings		4,529					4,665					4,898
	Interest expense, noninsurance operations		(198		)			(198		)			(184		)
	Corporate and eliminations		(78		)			(68		)			(56		)
	Pretax operating earnings		4,253					4,399					4,658
	Realized investment gains (losses)		171			(1)		389			(1)		(349		)
	Other non-operating income (loss)		67					28					(7		)
	Total earnings before income taxes		$	4,491				$	4,816				$	4,302
	Income taxes applicable to pretax operating earnings		$	1,456				$	1,512				$	1,561
	Effect of foreign currency translation on operating earnings		(117		)			(357		)			8
	(1) Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations
Reconciliation of Assets from Segment to Consolidated	Assets as of December 31 were as follows:
	(In millions)	2014					2013					2012
	Assets:
	Aflac Japan		$	98,525				$	102,973				$	113,678
	Aflac U.S.		18,383					16,112					16,122
	Other business segments		128					155					154
	Total business segment assets		117,036					119,240					129,954
	Corporate		24,636					19,909					20,318
	Intercompany eliminations		(21,905		)			(17,842		)			(19,178		)
	Total assets		$	119,767				$	121,307				$	131,094
Foreign Currency Disclosure	Yen-Translation Effects: The following table shows the yen/dollar exchange rates used for or during the periods ended December 31. Exchange effects were calculated using the same yen/dollar exchange rate for the current year as for each respective prior year.
		2014					2013					2012
	Statements of Earnings:
	Weighted-average yen/dollar exchange rate		105.46					97.54					79.81
	Yen percent strengthening (weakening)		(7.5		)%			(18.2		)%			(.1		)%
	Exchange effect on pretax operating earnings (in millions)		$	(180	)			$	(534	)			$	11
		2014					2013
	Balance Sheets:
	Yen/dollar exchange rate at December 31		120.55					105.39
	Yen percent strengthening (weakening)		(12.6		)%			(17.8		)%
	Exchange effect on total assets (in millions)		$	(10,706	)			$	(17,836	)
	Exchange effect on total liabilities (in millions)		(12,025		)			(19,806		)
Schedule of Intercompany Transfers of Funds	Information on transfers for each of the years ended December 31 is shown below. See Note 13 for information concerning restrictions on transfers from Aflac Japan.
	(In millions)	2014					2013					2012
	Management fees		$	39				$	37				$	30
	Allocated expenses		71					74					58
	Profit repatriation		1,704					771					422
	Total transfers from Aflac Japan		$	1,814				$	882				$	510
Property, Plant and Equipment	Classes of property and equipment as of December 31 were as follows:
	(In millions)	2014					2013
	Property and equipment:
	Land		$	168				$	168
	Buildings		393					444
	Equipment and furniture		305					329
	Total property and equipment		866					941
	Less accumulated depreciation		437					460
	Net property and equipment		$	429				$	481

INVESTMENTS_Tables

INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
Schedule Of Net Investment Income	The components of net investment income for the years ended December 31 were as follows:
	(In millions)	2014						2013						2012
	Fixed-maturity securities		$	3,249					$	3,210					$	3,248
	Perpetual securities		141						153						253
	Equity securities and other		7						7						17
	Short-term investments and cash equivalents		2						1						2
	Gross investment income		3,399						3,371						3,520
	Less investment expenses		80						78						47
	Net investment income		$	3,319					$	3,293					$	3,473
Available-for-sale Securities	The amortized cost for our investments in debt and perpetual securities, the cost for equity securities and the fair values of these investments at December 31 are shown in the following tables.
		2014
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	17,341					$	1,740					$	0					$	19,081
	Municipalities		88						9						0						97
	Mortgage- and asset-backed securities		351						35						0						386
	Public utilities		1,691						226						5						1,912
	Sovereign and supranational		799						163						0						962
	Banks/financial institutions		2,752						325						189						2,888
	Other corporate		3,479						531						48						3,962
	Total yen-denominated		26,501						3,029						242						29,288
	Dollar-denominated:
	U.S. government and agencies		100						17						0						117
	Municipalities		961						201						2						1,160
	Mortgage- and asset-backed securities		185						31						0						216
	Public utilities		5,061						960						36						5,985
	Sovereign and supranational		343						111						0						454
	Banks/financial institutions		2,943						775						8						3,710
	Other corporate		22,291						2,682						330						24,643
	Total dollar-denominated		31,884						4,777						376						36,285
	Total fixed maturities		58,385						7,806						618						65,573
	Perpetual securities:
	Yen-denominated:
	Banks/financial institutions		2,132						223						92						2,263
	Other corporate		183						48						0						231
	Dollar-denominated:
	Banks/financial institutions		125						50						0						175
	Total perpetual securities		2,440						321						92						2,669
	Equity securities		19						9						0						28
	Total securities available for sale		$	60,844					$	8,136					$	710					$	68,270
		2013
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	14,936					$	431					$	33					$	15,334
	Mortgage- and asset-backed securities		558						29						0						587
	Public utilities		2,261						100						18						2,343
	Sovereign and supranational		978						85						28						1,035
	Banks/financial institutions		2,799						220						242						2,777
	Other corporate		3,956						151						185						3,922
	Total yen-denominated		25,488						1,016						506						25,998
	Dollar-denominated:
	U.S. government and agencies		92						10						4						98
	Municipalities		992						71						12						1,051
	Mortgage- and asset-backed securities		163						21						0						184
	Public utilities		4,931						471						183						5,219
	Sovereign and supranational		404						85						1						488
	Banks/financial institutions		3,318						447						33						3,732
	Other corporate		21,123						1,347						1,170						21,300
	Total dollar-denominated		31,023						2,452						1,403						32,072
	Total fixed maturities		56,511						3,468						1,909						58,070
	Perpetual securities:
	Yen-denominated:
	Banks/financial institutions		2,582						151						217						2,516
	Other corporate		209						0						0						209
	Dollar-denominated:
Banks/financial institutions		196						35						9						222
Total perpetual securities		2,987						186						226						2,947
Equity securities		17						5						1						21
Total securities available for sale		$	59,515					$	3,659					$	2,136					$	61,038
Held-to-maturity Securities
		2014
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities held to maturity, carried at amortized cost:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	20,023					$	3,195					$	0					$	23,218
	Municipalities		346						71						0						417
	Mortgage- and asset-backed securities		43						3						0						46
	Public utilities		3,342						281						20						3,603
	Sovereign and supranational		2,556						272						14						2,814
	Banks/financial institutions		4,932						231						78						5,085
	Other corporate		3,000						326						12						3,314
	Total yen-denominated		34,242						4,379						124						38,497
	Total securities held to maturity		$	34,242					$	4,379					$	124					$	38,497
		2013
	(In millions)	Cost or						Gross						Gross						Fair
		Amortized						Unrealized						Unrealized						Value
		Cost						Gains						Losses
	Securities held to maturity, carried at amortized cost:
	Fixed maturities:
	Yen-denominated:
	Japan government and agencies		$	27,362					$	1,347					$	1					$	28,708
	Municipalities		399						41						0						440
	Mortgage- and asset-backed securities		58						3						0						61
	Public utilities		3,900						150						122						3,928
	Sovereign and supranational		2,941						171						72						3,040
	Banks/financial institutions		6,310						146						328						6,128
	Other corporate		3,445						183						87						3,541
	Total yen-denominated		44,415						2,041						610						45,846
	Total securities held to maturity		$	44,415					$	2,041					$	610					$	45,846
Investments Classified by Contractual Maturity Date	The contractual maturities of our investments in fixed maturities at December 31, 2014, were as follows:
		Aflac Japan												Aflac U.S.
	(In millions)	Amortized						Fair						Amortized						Fair
		Cost						Value						Cost						Value
	Available for sale:
	Due in one year or less		$	369					$	390					$	65					$	69
	Due after one year through five years		1,519						1,771						628						724
	Due after five years through 10 years		10,351						10,979						1,472						1,561
	Due after 10 years		34,018						38,595						9,103						10,540
	Mortgage- and asset-backed securities		405						461						36						46
	Total fixed maturities available for sale		$	46,662					$	52,196					$	11,304					$	12,940
	Held to maturity:
	Due after one year through five years		1,520						1,631						0						0
	Due after five years through 10 years		1,937						2,130						0						0
	Due after 10 years		30,742						34,690						0						0
	Mortgage- and asset-backed securities		43						46						0						0
	Total fixed maturities held to maturity		$	34,242					$	38,497					$	0					$	0
Economic Maturities of Investments in Perpetual Securities	The economic maturities of our investments in perpetual securities, which were all reported as available for sale at December 31, 2014, were as follows:
		Aflac Japan												Aflac U.S.
	(In millions)	Amortized						Fair						Amortized						Fair
		Cost						Value						Cost						Value
	Due in one year or less		$	306					$	300					$	5					$	5
	Due after one year through five years		624						674						0						0
	Due after 10 years		1,466						1,635						39						55
	Total perpetual securities available for sale		$	2,396					$	2,609					$	44					$	60
Investment Exposures Exceeding 10 Percent Shareholders Equity	Investment exposures that individually exceeded 10% of shareholders' equity as of December 31 were as follows:
		2014						2013
	(In millions)	Credit		Amortized		Fair		Credit		Amortized		Fair
		Rating		Cost		Value		Rating		Cost		Value
	Japan National Government(1)	A		$37,021		$41,878		AA		$41,924		$43,619
	(1)JGBs or JGB-backed securities
Bank and Financial Institution Investments	Our total investments in the bank and financial institution sector as of December 31, including those classified as perpetual securities, were as follows:
		2014											2013
		Total Investments in						Percentage of					Total Investments in						Percentage of
		Banks and Financial						Total Investment					Banks and Financial						Total Investment
		Institutions Sector						Portfolio					Institutions Sector						Portfolio
		(in millions)											(in millions)
	Fixed maturities:
	Amortized cost		$	10,627					11	%				$	12,427					12	%
	Fair value		11,683						11					12,637						12
	Perpetual securities:
	Upper Tier II:
	Amortized cost		$	1,554					2	%				$	1,920					2	%
	Fair value		1,645						1					1,913						2
	Tier I:
	Amortized cost		703						1					858						1
	Fair value		793						1					825						1
	Total:
	Amortized cost		$	12,884					14	%				$	15,205					15	%
	Fair value		14,121						13					15,375						15
Gain (Loss) on Investments	Information regarding pretax realized gains and losses from investments for the years ended December 31 follows:
	(In millions)	2014				2013				2012
	Realized investment gains (losses) on securities:
	Fixed maturities:
	Available for sale:
	Gross gains from sales	$	192			$	316			$	427
	Gross losses from sales	(12		)		(87		)		(48		)
	Net gains (losses) from redemptions	34				34				2
	Other-than-temporary impairment losses	(31		)		(128		)		(734		)
	Held to maturity:
	Net gains (losses) from redemptions	1				0				4
	Total fixed maturities	184				135				(349		)
	Perpetual securities:
	Available for sale:
	Gross gains from sales	0				0				127
	Gross losses from sales	0				(1		)		(98		)
	Net gains (losses) from redemptions	0				0				60
	Other-than-temporary impairment losses	0				(70		)		(243		)
	Total perpetual securities	0				(71		)		(154		)
	Equity securities:
	Other-than-temporary impairment losses	0				(1		)		0
	Total equity securities	0				(1		)		0
	Derivatives and other:
	Derivative gains (losses)	31				326				151
	Other	0				10				3
	Total derivatives and other	31				336				154
	Total realized investment gains (losses)	$	215			$	399			$	(349	)
Other Than Temporary Impairment Losses on Investment Securities	The following table details our pretax other-than-temporary impairment losses by investment category that resulted from our impairment evaluation process for the years ended December 31.
	(In millions)	2014				2013				2012
	Perpetual securities	$	0			$	70			$	243
	Corporate bonds	31				102				345
	Mortgage- and asset-backed securities	0				0				3
	Sovereign and supranational	0				26				386
	Equity securities	0				1				0
	Total other-than-temporary impairment losses realized (1)	$	31			$	199			$	977
	(1) Includes $45 and $597 for the years ended December 31, 2013 and 2012, respectively, for credit-related impairments;
	$26 and $27 for the years ended December 31, 2013 and 2012, respectively, for impairments due to severity and duration
	of decline in fair value; and $31, $128 and $353 for the years ended December 31, 2014, 2013 and 2012, respectively, from change
	in intent to sell securities
Unrealized Gain (Loss) on Investments	Information regarding changes in unrealized gains and losses from investments for the years ended December 31 follows:
	(In millions)	2014						2013						2012
	Changes in unrealized gains (losses):
	Fixed maturities:
	Available for sale		$	5,629					$	(2,281	)				$	1,624
	Transferred to held to maturity		(10		)				(9		)				(14		)
	Perpetual securities:
	Available for sale		269						(129		)				547
	Equity securities		5						1						0
	Total change in unrealized gains (losses)		$	5,893					$	(2,418	)				$	2,157
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 investment securities at December 31 was as follows:
	(In millions)	2014						2013
	Unrealized gains (losses) on securities available for sale		$	7,426					$	1,523
	Unamortized unrealized gains on securities transferred to held to maturity		0						11
	Deferred income taxes		(2,754		)				(499		)
	Shareholders’ equity, unrealized gains (losses) on investment securities		$	4,672					$	1,035
Investments Gross Unrealized Loss Aging	The following tables show the fair values and gross unrealized losses of our available-for-sale and held-to-maturity investments 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 at December 31.
		2014
		Total												Less than 12 months											12 months or longer
	(In millions)	Fair						Unrealized						Fair						Unrealized					Fair					Unrealized
		Value						Losses						Value						Losses					Value					Losses
	Fixed Maturities:
	Municipalities:
	Dollar-denominated		75						2						53						1					22					1
	Public utilities:
	Dollar-denominated		1,001						36						164						7					837					29
	Yen-denominated		805						25						98						1					707					24
	Sovereign and supranational:
	Yen-denominated		359						14						0						0					359					14
	Banks/financial institutions:
	Dollar-denominated		205						8						53						5					152					3
	Yen-denominated		1,828						267						166						0					1,662					267
	Other corporate:
	Dollar-denominated		8,072						330						1,901						62					6,171					268
	Yen-denominated		1,151						60						122						2					1,029					58
	Total fixed maturities		13,496						742						2,557						78					10,939					664
	Perpetual securities:
	Yen-denominated		783						92						194						5					589					87
	Total perpetual securities		783						92						194						5					589					87
	Total		$	14,279					$	834					$	2,751					$	83				$	11,528				$	751
		2013
		Total												Less than 12 months											12 months or longer
	(In millions)	Fair						Unrealized						Fair						Unrealized					Fair					Unrealized
		Value						Losses						Value						Losses					Value					Losses
	Fixed Maturities:
	Japan government and agencies:
	Yen-denominated		$	8,869					$	34					$	8,869					$	34				$	0				$	0
	Municipalities:
	Dollar-denominated		177						12						145						8					32					4
	Public utilities:
	Dollar-denominated		2,023						183						1,740						143					283					40
	Yen-denominated		2,519						140						1,816						54					703					86
	Sovereign and supranational:
	Dollar-denominated		12						1						12						1					0					0
	Yen-denominated		1,152						100						791						34					361					66
	Banks/financial institutions:
	Dollar-denominated		547						33						454						23					93					10
	Yen-denominated		4,533						570						2,322						107					2,211					463
	Other corporate:
	Dollar-denominated		11,588						1,170						8,504						733					3,084					437
	Yen-denominated		3,372						272						2,296						152					1,076					120
	U.S. government and agencies:
	Dollar-denominated		36						4						36						4					0					0
	Total fixed maturities		34,828						2,519						26,985						1,293					7,843					1,226
	Perpetual securities:
	Dollar-denominated		59						9						52						8					7					1
	Yen-denominated		1,322						217						748						74					574					143
	Total perpetual securities		1,381						226						800						82					581					144
	Equity securities		5						1						5						1					0					0
	Total		$	36,214					$	2,746					$	27,790					$	1,376				$	8,424				$	1,370
Investments in Unrealized Loss Position	The following table provides more information on our unrealized loss position as of December 31.
		2014												2013
	(In millions)	Investments				Gross				Gross				Investments				Gross				Gross
		in an Unrealized				Unrealized				Unrealized				in an Unrealized				Unrealized				Unrealized
		Loss Position				Losses				Losses that are Investment Grade				Loss Position				Losses				Losses that are Investment Grade
	Fixed Maturities:
	Japan government		0	%			0	%			0	%			25	%			1	%			100	%
	and agencies
	Public utilities		13				7				100				13				12				98
	Sovereign and		3				2				100				3				4				100
	supranational
	Banks/financial		14				33				31				14				22				64
	institutions
	Other corporate		65				47				88				41				53				91
	Total fixed		95	%			89	%							96	%			92	%
	maturities
	Perpetual securities		5				11				100				4				8				90
	Total		100	%			100	%							100	%			100	%
Variable Interest Entity, Consolidated
Investments in Variable Interest Entities	The following table presents the amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported as of December 31.
	Investments in Consolidated Variable Interest Entities
		2014												2013
	(In millions)	Amortized						Fair						Amortized						Fair
		Cost						Value						Cost						Value
	Assets:
	Fixed maturities, available for sale		$	3,020					$	4,166					$	4,109					$	4,843
	Perpetual securities, available for sale		405						429						463						468
	Fixed maturities, held to maturity		83						84						237						236
	Other assets		106						106						106						106
	Total assets of consolidated VIEs		$	3,614					$	4,785					$	4,915					$	5,653
	Liabilities:
	Other liabilities		$	318					$	318					$	207					$	207
	Total liabilities of consolidated VIEs		$	318					$	318					$	207					$	207
Variable Interest Entity, Not Consolidated
Investments in Variable Interest Entities	The table below reflects the amortized cost, fair value and balance sheet caption in which our investment in VIEs not consolidated are reported as of December 31.
	Investments in Variable Interest Entities Not Consolidated
		2014												2013
	(In millions)	Amortized						Fair						Amortized						Fair
		Cost						Value						Cost						Value
	Assets:
	Fixed maturities, available for sale		$	6,104					$	6,937					$	6,724					$	6,916
	Perpetual securities, available for sale		324						330						370						378
	Fixed maturities, held to maturity		2,564						2,829						2,949						3,039
	Total investments in VIEs not consolidated		$	8,992					$	10,096					$	10,043					$	10,333
Perpetual securities
Schedule of Available-for-sale Securities Reconciliation	Details of our holdings of perpetual securities as of December 31 were as follows:
	Perpetual Securities
				2014																		2013
	(In millions)	Credit		Amortized						Fair						Unrealized						Amortized					Fair					Unrealized
		Rating		Cost						Value						Gain (Loss)						Cost					Value					Gain (Loss)
	Upper Tier II:
		A			$	61					$	87					$	26					$	145				$	183				$	38
		BBB			1,330						1,333						3						1,563					1,532					(31		)
		BB or lower			163						225						62						212					198					(14		)
	Total Upper Tier II				1,554						1,645						91						1,920					1,913					(7		)
	Tier I:
		BBB			519						556						37						746					706					(40		)
		BB or lower			184						237						53						112					119					7
	Total Tier I				703						793						90						858					825					(33		)
	Other subordinated
	- non-banks:
		BB or lower			183						231						48						209					209					0
	Total				$	2,440					$	2,669					$	229					$	2,987				$	2,947				$	(40	)

DERIVATIVE_INSTRUMENTS_Tables

DERIVATIVE INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value and Notional Amount of Derivatives with Counterparty Credit Risk	The counterparties to these derivatives are financial institutions with the following credit ratings as of December 31:
		2014															2013
	(In millions)	Notional Amount					Asset Derivatives					Liability Derivatives					Notional Amount					Asset Derivatives					Liability Derivatives
		of Derivatives					Fair Value					Fair Value					of Derivatives					Fair Value					Fair Value
	Counterparties' credit rating:
	AA		$	1,098				$	39				$	(36	)			$	161				$	1				$	(7	)
	A		22,564					763					(2,387		)			22,314					487					(830		)
	Total		$	23,662				$	802				$	(2,423	)			$	22,475				$	488				$	(837	)
Maximum Potential Risk, Fair Value, Weighted Average Years to Maturity, and Underlying Referenced Credit Obligation Type for Credit Derivatives	The following tables present the maximum potential risk, fair value, weighted-average years to maturity, and underlying referenced credit obligation type for credit default swaps within consolidated VIE structures as of December 31.
	2014
			Less than								One to								Three to								Five to								Total
			one year								three years								five years								ten years
	(In millions)	Credit	Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum			Estimated
		Rating	potential				fair value				potential				fair value				potential				fair value				potential				fair value				potential			fair value
			risk								risk								risk								risk								risk
	Index exposure:
	Corporate bonds:
		A	$	0			$	0			$	0			$	0			$	(83	)		$	0			$	0			$	0			$	(83	)	$	0
	Total		$	0			$	0			$	0			$	0			$	(83	)		$	0			$	0			$	0			$	(83	)	$	0
	2013
			Less than								One to								Three to								Five to								Total
			one year								three years								five years								ten years
	(In millions)	Credit	Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum				Estimated				Maximum			Estimated
		Rating	potential				fair value				potential				fair value				potential				fair value				potential				fair value				potential			fair value
			risk								risk								risk								risk								risk
	Index exposure:
	Corporate bonds:
		A	$	0			$	0			$	(112	)		$	1			$	0			$	0			$	0			$	0			$	(112	)	$	1
		BBB	0				0				0				0				0				0				(95		)		(4		)		(95		)	(4		)
	Total		$	0			$	0			$	(112	)		$	1			$	0			$	0			$	(95	)		$	(4	)		$	(207	)	$	(3	)
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value
		2014
	(In millions)	Net Derivatives												Asset						Liability
														Derivatives						Derivatives
	Hedge Designation/ Derivative Type	Notional						Fair Value						Fair Value						Fair Value
		Amount
	Cash flow hedges:
	Foreign currency swaps		$	75					$	(15	)				$	0					$	(15	)
	Total cash flow hedges		75						(15		)				0						(15		)
	Fair value hedges:
	Foreign currency forwards		12,388						(1,791		)				0						(1,791		)
	Foreign currency options		697						(32		)				0						(32		)
	Interest rate swaptions		2,502						(159		)				0						(159		)
	Total fair value hedges		15,587						(1,982		)				0						(1,982		)
	Net investment hedge:
	Foreign currency forwards		1,307						54						56						(2		)
	Total net investment hedge		1,307						54						56						(2		)
	Non-qualifying strategies:
	Foreign currency swaps		5,765						443						746						(303		)
	Credit default swaps		83						0						0						0
	Foreign currency forwards		784						(119		)				0						(119		)
	Foreign currency options		53						(1		)				0						(1		)
	Interest rate swaptions		8						(1		)				0						(1		)
	Total non-qualifying strategies		6,693						322						746						(424		)
	Total derivatives		$	23,662					$	(1,621	)				$	802					$	(2,423	)
	Balance Sheet Location
	Other assets		$	6,531					$	802					$	802					$	0
	Other liabilities		17,131						(2,423		)				0						(2,423		)
	Total derivatives		$	23,662					$	(1,621	)				$	802					$	(2,423	)
		2013
	(In millions)	Net Derivatives												Asset						Liability
														Derivatives						Derivatives
	Hedge Designation/ Derivative Type	Notional						Fair Value						Fair Value						Fair Value
		Amount
	Cash flow hedges:
	Foreign currency swaps		$	75					$	3					$	3					$	0
	Interest rate swaps		52						0						0						0
	Total cash flow hedges		127						3						3						0
	Fair value hedges:
	Foreign currency forwards		11,249						(582		)				0						(582		)
	Interest rate swaptions		4,500						(12		)				20						(32		)
	Total fair value hedges		15,749						(594		)				20						(614		)
	Net investment hedge:
	Foreign currency forwards		356						17						17						0
	Foreign currency options		95						3						4						(1		)
	Total net investment hedge		451						20						21						(1		)
	Non-qualifying strategies:
	Foreign currency swaps		5,829						224						442						(218		)
	Credit default swaps		207						(3		)				1						(4		)
	Interest rate swaps		112						1						1						0
	Total non-qualifying strategies		6,148						222						444						(222		)
	Total derivatives		$	22,475					$	(349	)				$	488					$	(837	)
	Balance Sheet Location
	Other assets		$	5,308					$	488					$	488					$	0
	Other liabilities		17,167						(837		)				0						(837		)
	Total derivatives		$	22,475					$	(349	)				$	488					$	(837	)
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 for the years ended December 31.
	Fair Value Hedging Relationships
	(In millions)			Hedging Derivatives												Hedged Items
	Hedging Derivatives	Hedged Items		Total				Gains (Losses)				Gains (Losses)				Gains (Losses)				Ineffectiveness
				Gains (Losses)				Excluded from Effectiveness Testing				Included in Effectiveness Testing								Recognized for Fair Value Hedge
	2014:00:00
	Foreign currency forwards	Fixed-maturity securities		$	(1,835	)		$	(38	)		$	(1,797	)		$	1,819			$	22
	Foreign currency options	Fixed-maturity securities		(41		)		(4		)		(37		)		38				1
	Interest rate	Fixed-maturity securities		(318		)		(36		)		(282		)		316				34
	swaptions
	2013:00:00
	Foreign currency	Fixed-maturity securities		$	(1,735	)		$	(25	)		$	(1,710	)		$	1,700			$	(10	)
	forwards
	Interest rate	Fixed-maturity securities		17				17				0				0				0
	swaptions
	2012:00:00
	Foreign currency	Fixed-maturity securities		$	(535	)		$	(8	)		$	(527	)		$	528			$	1
	forwards
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance	The following table summarizes the impact to realized investment gains (losses) and other comprehensive income (loss) from all derivatives and hedging instruments for the years ended December 31.
		2014										2013										2012
	(In millions)	Realized Investment					Other					Realized Investment					Other					Realized					Other
		Gains (Losses)					Comprehensive					Gains (Losses)					Comprehensive					Investment					Comprehensive
							Income (Loss)(1)										Income (Loss)(1)					Gains (Losses)					Income (Loss)(1)
	Qualifying hedges:
	Cash flow hedges:
	Foreign currency swaps		$	(2	)			$	(17	)			$	(2	)			$	(10	)			$	(3	)			$	(22	)
	Total cash flow hedges		(2		)			(17		)			(2		)			(10		)			(3		)			(22		)
	Fair value hedges:
	Foreign currency forwards (2)		(16		)			0					(35		)			0					(7		)			0
	Foreign currency options (2)		(3		)			0					0					0					0					0
	Interest rate swaptions (2)		(2		)			0					17					0					0					0
	Total fair value hedges		(21		)			0					(18		)			0					(7		)			0
	Net investment hedge:
	Non-derivative hedging		0					39					0					155					0					96
	instruments
	Foreign currency swaps		0					0					0					(104		)			0					0
	Foreign currency forwards		0					89					0					24					0					0
	Foreign currency options		0					(3		)			0					4					0					0
	Total net investment hedge		0					125					0					79					0					96
	Non-qualifying strategies:
	Foreign currency swaps		151					0					346					0					111					0
	Foreign currency forwards		(11		)			0					0					0					0					0
	Foreign currency options		0					0					11					0					0					0
	Credit default swaps		3					0					31					0					64					0
	Interest rate swaps		(1		)			0					(8		)			0					(14		)			0
	Interest rate swaptions		1					0					(29		)			0					0					0
	Futures		(89		)			0					(5		)			0					0					0
	Total non- qualifying strategies		54					0					346					0					161					0
	Total		$	31				$	108				$	326				$	69				$	151				$	74
	(1) Cash flow hedge items 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 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
	2014
																				Gross Amounts Not Offset
																				in Balance Sheet
	(In millions)	Gross Amount of Recognized Assets						Gross Amount						Net Amount of Assets Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Received						Net Amount
								Offset in
								Balance Sheet
	Derivative assets:
	Foreign currency swaps		$	746					$	0					$	746					$	0				$	(568	)				$	178
	Foreign currency forwards		56						0						56						0					(51		)				5
	Total derivative assets,		802						0						802						0					(619		)	(1)			183
	subject to a master
	netting arrangement
	or offsetting
	arrangement
	Securities lending and		2,149						0						2,149						0					(2,149		)				0
	similar arrangements
	Total		$	2,951					$	0					$	2,951					$	0				$	(2,768	)				$	183
	(1) Consists of $153 of pledged securities and $466 of cash.
	2013
																				Gross Amounts Not Offset
																				in Balance Sheet
	(In millions)	Gross Amount of Recognized Assets						Gross Amount Offset in Balance Sheet						Net Amount of Assets Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Received						Net Amount
	Derivative assets:
	Foreign currency swaps		$	445					$	0					$	445					$	0				$	(276	)				$	169
	Foreign currency forwards		17						0						17						0					(16		)				1
	Foreign currency options		4						0						4						0					(3		)				1
	Credit default swaps		1						0						1						0					0						1
	Interest rate swaps		1						0						1						0					0						1
	Interest rate swaptions		20						0						20						0					0						20
	Total derivative assets,		488						0						488						0					(295		)	(1)			193
	subject to a master
	netting arrangement
	or offsetting
	arrangement
	Securities lending and		5,656						0						5,656						0					(5,656		)				0
	similar arrangements
	Total		$	6,144					$	0					$	6,144					$	0				$	(5,951	)				$	193
	(1) Consists entirely of cash.
Offsetting Liabilities	Offsetting of Financial Liabilities and Derivative Liabilities
	2014
																				Gross Amounts Not Offset
																				in Balance Sheet
	(In millions)	Gross Amount of Recognized Liabilities						Gross Amount Offset in Balance Sheet						Net Amount of Liabilities Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Pledged						Net Amount
	Derivative liabilities:
	Foreign currency swaps		$	(318	)				$	0					$	(318	)				$	0				$	0					$	(318	)
	Foreign currency forwards		(1,912		)				0						(1,912		)				0					1,439						(473		)
	Foreign currency options		(33		)				0						(33		)				0					24						(9		)
	Interest rate swaptions		(160		)				0						(160		)				0					158						(2		)
	Total derivative liabilities,		(2,423		)				0						(2,423		)				0					1,621			(1)			(802		)
	subject to a master
	netting arrangement
	or offsetting
	arrangement
	Securities lending and		(2,193		)				0						(2,193		)				2,149					0						(44		)
	similar arrangements
	Total		$	(4,616	)				$	0					$	(4,616	)				$	2,149				$	1,621					$	(846	)
	(1) Consists entirely of pledged securities.
	2013
																				Gross Amounts Not Offset
																				in Balance Sheet
	(In millions)	Gross Amount of Recognized Liabilities						Gross Amount Offset in Balance Sheet						Net Amount of Liabilities Presented in Balance Sheet						Carrying Value of Financial Instruments					Collateral Pledged						Net Amount
	Derivative liabilities:
	Foreign currency swaps		$	(218	)				$	0					$	(218	)				$	0				$	1					$	(217	)
	Foreign currency forwards		(582		)				0						(582		)				0					0						(582		)
	Foreign currency options		(1		)				0						(1		)				0					0						(1		)
	Credit default swaps		(4		)				0						(4		)				0					0						(4		)
	Interest rate swaptions		(32		)				0						(32		)				0					7						(25		)
	Total derivative liabilities,		(837		)				0						(837		)				0					8			(1)			(829		)
	subject to a master
	netting arrangement
	or offsetting
	arrangement
	Securities lending and		(5,820		)				0						(5,820		)				5,656					0						(164		)
	similar arrangements
	Total		$	(6,657	)				$	0					$	(6,657	)				$	5,656				$	8					$	(993	)
	(1) Consists of $7 of pledged securities and $1 of cash.

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
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 as of December 31.
		2014
	(In millions)	Quoted Prices in						Significant						Significant						Total
		Active Markets						Observable						Unobservable						Fair
		for Identical						Inputs						Inputs						Value
		Assets						(Level 2)						(Level 3)
		(Level 1)
	Assets:
	Securities available for sale, carried at
	fair value:
	Fixed maturities:
	Government and agencies		$	18,683					$	515					$	0					$	19,198
	Municipalities		0						1,257						0						1,257
	Mortgage- and asset-backed securities		0						379						223						602
	Public utilities		0						7,897						0						7,897
	Sovereign and supranational		0						1,416						0						1,416
	Banks/financial institutions		0						6,572						26						6,598
	Other corporate		0						28,605						0						28,605
	Total fixed maturities		18,683						46,641						249						65,573
	Perpetual securities:
	Banks/financial institutions		0						2,289						149						2,438
	Other corporate		0						231						0						231
	Total perpetual securities		0						2,520						149						2,669
	Equity securities		19						6						3						28
	Other assets:
	Foreign currency swaps		0						640						106						746
	Foreign currency forwards		0						56						0						56
	Total other assets		0						696						106						802
	Other investments		171						0						0						171
	Cash and cash equivalents		4,658						0						0						4,658
	Total assets		$	23,531					$	49,863					$	507					$	73,901
	Liabilities:
	Foreign currency swaps		$	0					$	0					$	318					$	318
	Foreign currency forwards		0						1,912						0						1,912
	Foreign currency options		0						33						0						33
	Interest rate swaptions		0						160						0						160
	Total liabilities		$	0					$	2,105					$	318					$	2,423
		2013
	(In millions)	Quoted Prices in						Significant						Significant						Total
		Active Markets						Observable						Unobservable						Fair
		for Identical						Inputs						Inputs						Value
		Assets						(Level 2)						(Level 3)
		(Level 1)
	Assets:
	Securities available for sale, carried at
	fair value:
	Fixed maturities:
	Government and agencies		$	14,928					$	504					$	0					$	15,432
	Municipalities		0						1,051						0						1,051
	Mortgage- and asset-backed securities		0						402						369						771
	Public utilities		0						7,562						0						7,562
	Sovereign and supranational		0						1,523						0						1,523
	Banks/financial institutions		0						6,486						23						6,509
	Other corporate		0						25,222						0						25,222
	Total fixed maturities		14,928						42,750						392						58,070
	Perpetual securities:
	Banks/financial institutions		0						2,686						52						2,738
	Other corporate		0						209						0						209
	Total perpetual securities		0						2,895						52						2,947
	Equity securities		14						4						3						21
	Other assets:
	Foreign currency swaps		0						341						104						445
	Foreign currency forwards		0						17						0						17
	Foreign currency options		0						4						0						4
Credit default swaps		0						0						1						1
Interest rate swaps		0						0						1						1
Interest rate swaptions		0						20						0						20
Total other assets		0						382						106						488
Other investments		463						0						0						463
Cash and cash equivalents		2,543						0						0						2,543
Total assets		$	17,948					$	46,031					$	553					$	64,532
Liabilities:
Foreign currency swaps		$	0					$	15					$	203					$	218
Foreign currency forwards		0						582						0						582
Foreign currency options		0						1						0						1
Credit default swaps		0						0						4						4
Interest rate swaptions		0						32						0						32
Total liabilities		$	0					$	630					$	207					$	837
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 as of December 31.
		2014
	(In millions)	Carrying					Quoted Prices in						Significant						Significant					Total
		Value					Active Markets						Observable						Unobservable					Fair
							for Identical						Inputs						Inputs					Value
							Assets						(Level 2)						(Level 3)
							(Level 1)
	Assets:
	Securities held to maturity,
	carried at amortized cost:
	Fixed maturities:
	Government and agencies		$	20,023				$	23,218					$	0					$	0					$	23,218
	Municipalities		346					0						417						0						417
	Mortgage and asset-backed		43					0						15						31						46
	securities
	Public utilities		3,342					0						3,603						0						3,603
	Sovereign and		2,556					0						2,814						0						2,814
	supranational
	Banks/financial institutions		4,932					0						5,085						0						5,085
	Other corporate		3,000					0						3,314						0						3,314
	Total assets		$	34,242				$	23,218					$	15,248					$	31					$	38,497
	Liabilities:
	Other policyholders’ funds		$	6,031				$	0					$	0					$	5,905					$	5,905
	Notes payable		5,268					0						0						5,835						5,835
	(excluding capital leases)
	Total liabilities		$	11,299				$	0					$	0					$	11,740					$	11,740
							2013
	(In millions)	Carrying					Quoted Prices in						Significant						Significant						Total
		Value					Active Markets						Observable						Unobservable						Fair
							for Identical						Inputs						Inputs						Value
							Assets						(Level 2)						(Level 3)
							(Level 1)
	Assets:
	Securities held to maturity,
	carried at amortized cost:
	Fixed maturities:
	Government and agencies		$	27,362				$	28,708					$	0					$	0					$	28,708
	Municipalities		399					0						440						0						440
	Mortgage and asset-backed		58					0						20						41						61
	securities
	Public utilities		3,900					0						3,928						0						3,928
	Sovereign and		2,941					0						3,040						0						3,040
	supranational
	Banks/financial institutions		6,310					0						6,128						0						6,128
	Other corporate		3,445					0						3,541						0						3,541
	Total assets		$	44,415				$	28,708					$	17,097					$	41					$	45,846
	Liabilities:
	Other policyholders’ funds		$	5,861				$	0					$	0					$	5,715					$	5,715
	Notes payable		4,891					0						0						5,241						5,241
	(excluding capital leases)
	Total liabilities		$	10,752				$	0					$	0					$	10,956					$	10,956
Fair Value Assets Available-for-Sale Securities Primary Pricing Sources	The following tables present the pricing sources for the fair values of our fixed maturities, perpetual securities, and equity securities as of December 31.
			2014
	(In millions)		Quoted Prices in Active Markets for Identical Assets						Significant Observable Inputs						Significant Unobservable Inputs						Total
			(Level 1)						(Level 2)						(Level 3)						Fair
																					Value
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Government and agencies:
	Third party pricing vendor			$	18,683					$	515					$	0					$	19,198
	Total government and agencies			18,683						515						0						19,198
	Municipalities:
	Third party pricing vendor			0						1,257						0						1,257
	Total municipalities			0						1,257						0						1,257
	Mortgage- and asset-backed securities:
	Third party pricing vendor			0						379						0						379
	Broker/other			0						0						223						223
	Total mortgage- and asset-backed securities			0						379						223						602
	Public utilities:
	Third party pricing vendor			0						7,897						0						7,897
	Total public utilities			0						7,897						0						7,897
	Sovereign and supranational:
	Third party pricing vendor			0						1,416						0						1,416
	Total sovereign and supranational			0						1,416						0						1,416
	Banks/financial institutions:
	Third party pricing vendor			0						6,514						0						6,514
	Broker/other			0						58						26						84
	Total banks/financial institutions			0						6,572						26						6,598
	Other corporate:
	Third party pricing vendor			0						28,605						0						28,605
	Total other corporate			0						28,605						0						28,605
	Total fixed maturities			18,683						46,641						249						65,573
	Perpetual securities:
	Banks/financial institutions:
	Third party pricing vendor			0						2,289						0						2,289
	Broker/other			0						0						149						149
	Total banks/financial institutions			0						2,289						149						2,438
	Other corporate:
	Third party pricing vendor			0						231						0						231
	Total other corporate			0						231						0						231
	Total perpetual securities			0						2,520						149						2,669
	Equity securities:
	Third party pricing vendor			19						6						0						25
	Broker/other			0						0						3						3
	Total equity securities			19						6						3						28
	Total securities available for sale			$	18,702					$	49,167					$	401					$	68,270
			2013
	(In millions)		Quoted Prices in Active Markets						Significant Observable						Significant Unobservable Inputs						Total
			for Identical Assets						Inputs						(Level 3)						Fair
			(Level 1)						(Level 2)												Value
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Government and agencies:
	Third party pricing vendor			$	14,928					$	504					$	0					$	15,432
	Total government and agencies			14,928						504						0						15,432
	Municipalities:
	Third party pricing vendor			0						1,051						0						1,051
	Total municipalities			0						1,051						0						1,051
	Mortgage- and asset-backed securities:
	Third party pricing vendor			0						402						0						402
	Broker/other			0						0						369						369
	Total mortgage- and asset-backed securities			0						402						369						771
	Public utilities:
	Third party pricing vendor			0						7,562						0						7,562
	Total public utilities			0						7,562						0						7,562
Sovereign and supranational:
Third party pricing vendor			0						1,523						0						1,523
Total sovereign and supranational			0						1,523						0						1,523
Banks/financial institutions:
Third party pricing vendor			0						6,486						0						6,486
Broker/other			0						0						23						23
Total banks/financial institutions			0						6,486						23						6,509
Other corporate:
Third party pricing vendor			0						25,220						0						25,220
Broker/other			0						2						0						2
Total other corporate			0						25,222						0						25,222
Total fixed maturities			14,928						42,750						392						58,070
Perpetual securities:
Banks/financial institutions:
Third party pricing vendor			0						2,686						52						2,738
Total banks/financial institutions			0						2,686						52						2,738
Other corporate:
Third party pricing vendor			0						209						0						209
Total other corporate			0						209						0						209
Total perpetual securities			0						2,895						52						2,947
Equity securities:
Third party pricing vendor			14						4						0						18
Broker/other			0						0						3						3
Total equity securities			14						4						3						21
Total securities available for sale			$	14,942					$	45,649					$	447					$	61,038
Fair Value Assets Held-To-Maturity Securities Primary Pricing Sources
			2014
	(In millions)		Quoted Prices in Active Markets for Identical Assets						Significant Observable Inputs						Significant Unobservable Inputs						Total
			(Level 1)						(Level 2)						(Level 3)						Fair
																					Value
	Securities held to maturity, carried at amortized cost:
	Fixed maturities:
	Government and agencies:
	Third party pricing vendor			$	23,218					$	0					$	0					$	23,218
	Total government and agencies			23,218						0						0						23,218
	Municipalities:
	Third party pricing vendor			0						417						0						417
	Total municipalities			0						417						0						417
	Mortgage- and asset-backed securities:
	Third party pricing vendor			0						15						0						15
	Broker/other			0						0						31						31
	Total mortgage- and asset-backed securities			0						15						31						46
	Public utilities:
	Third party pricing vendor			0						3,603						0						3,603
	Total public utilities			0						3,603						0						3,603
	Sovereign and supranational:
	Third party pricing vendor			0						2,814						0						2,814
	Total sovereign and supranational			0						2,814						0						2,814
	Banks/financial institutions:
	Third party pricing vendor			0						5,085						0						5,085
	Total banks/financial institutions			0						5,085						0						5,085
	Other corporate:
	Third party pricing vendor			0						3,287						0						3,287
	Broker/other			0						27						0						27
	Total other corporate			0						3,314						0						3,314
	Total securities held to maturity			$	23,218					$	15,248					$	31					$	38,497
			2013
	(In millions)		Quoted Prices in Active Markets						Significant Observable						Significant Unobservable Inputs						Total
			for Identical Assets						Inputs						(Level 3)						Fair
			(Level 1)						(Level 2)												Value
	Securities held to maturity, carried at amortized cost:
	Fixed maturities:
	Government and agencies:
	Third party pricing vendor			$	28,708					$	0					$	0					$	28,708
	Total government and agencies			28,708						0						0						28,708
	Municipalities:
	Third party pricing vendor			0						440						0						440
	Total municipalities			0						440						0						440
	Mortgage- and asset-backed securities:
	Third party pricing vendor			0						20						0						20
	Broker/other			0						0						41						41
	Total mortgage- and asset-backed securities			0						20						41						61
	Public utilities:
	Third party pricing vendor			0						3,928						0						3,928
	Total public utilities			0						3,928						0						3,928
	Sovereign and supranational:
	Third party pricing vendor			0						3,040						0						3,040
	Total sovereign and supranational			0						3,040						0						3,040
	Banks/financial institutions:
	Third party pricing vendor			0						6,128						0						6,128
	Total banks/financial institutions			0						6,128						0						6,128
	Other corporate:
	Third party pricing vendor			0						3,509						0						3,509
	Broker/other			0						32						0						32
	Total other corporate			0						3,541						0						3,541
	Total securities held to maturity			$	28,708					$	17,097					$	41					$	45,846
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following tables present the changes in fair value of our available-for-sale investments and derivatives classified as Level 3 as of December 31.
	2014
		Fixed Maturities																				Perpetual				Equity			Derivatives(1)
																						Securities				Securities
	(In millions)	Mortgage-				Public				Sovereign				Banks/				Other				Banks/							Interest			Foreign			Credit			Total
		and				Utilities				and				Financial				Corporate				Financial							Rate			Currency			Default
		Asset-								Supranational				Institutions								Institutions							Swaps			Swaps			Swaps
		Backed
		Securities
	Balance, beginning of period	$	369			$	0			$	0			$	23			$	0			$	52			$	3		$	1		$	(99	)	$	(3	)	$	346
	Realized investment gains (losses) included	0				0				0				0				0				0				0			(1		)	(191		)	3			(189		)
	in earnings
	Unrealized gains (losses) included in other	(134		)		0				0				3				0				8				0			0			(17		)	0			(140		)
	comprehensive income (loss)
	Purchases, issuances, sales and settlements:
	Purchases	0				0				0				0				0				0				0			0			0			0			0
	Issuances	0				0				0				0				0				0				0			0			0			0			0
	Sales	0				0				0				0				0				(60		)		0			0			0			0			(60		)
	Settlements	(12		)		0				0				0				0				0				0			0			95			0			83
	Transfers into Level 3(2)	0				0				0				0				0				149				0			0			0			0			149
	Transfers out of Level 3	0				0				0				0				0				0				0			0			0			0			0
	Balance, end of period	$	223			$	0			$	0			$	26			$	0			$	149			$	3		$	0		$	(212	)	$	0		$	189
	Changes in unrealized gains (losses) relating	$	0			$	0			$	0			$	0			$	0			$	0			$	0		$	(1	)	$	(191	)	$	3		$	(189	)
	to Level 3 assets and liabilities still held at
	the end of the period included in realized
	investment gains (losses)
	(1) Derivative assets and liabilities are presented net
	(2) Due to use of estimated redemption price
	2013
		Fixed Maturities																				Perpetual				Equity			Derivatives(1)
																						Securities				Securities
	(In millions)	Mortgage-				Public				Sovereign				Banks/				Other				Banks/							Interest			Foreign			Credit			Total
		and				Utilities				and				Financial				Corporate				Financial							Rate			Currency			Default
		Asset-								Supranational				Institutions								Institutions							Swaps			Swaps			Swaps
		Backed
		Securities
	Balance, beginning of period	$	338			$	420			$	418			$	1,024			$	986			$	215			$	4		$	29		$	(172	)	$	(65	)	$	3,197
	Realized investment gains (losses) included	0				0				0				0				0				0				0			(8		)	84			29			105
	in earnings
	Unrealized gains (losses) included in other	(72		)		(20		)		0				(4		)		0				3				(1		)	0			(11		)	0			(105		)
	comprehensive income (loss)
	Purchases, issuances, sales and settlements:
	Purchases	0				0				0				0				0				0				0			0			0			0			0
	Issuances	0				0				0				0				0				0				0			0			0			0			0
	Sales	0				(400		)		0				0				0				0				0			(20		)	0			33			(387		)
	Settlements	(13		)		0				0				0				0				0				0			0			0			0			(13		)
	Transfers into Level 3(2)	125				0				0				0				0				49				0			0			0			0			174
	Transfers out of Level 3(3)	(9		)		0				(418		)		(997		)		(986		)		(215		)		0			0			0			0			(2,625		)
	Balance, end of period	$	369			$	0			$	0			$	23			$	0			$	52			$	3		$	1		$	(99	)	$	(3	)	$	346
	Changes in unrealized gains (losses) relating	$	0			$	0			$	0			$	0			$	0			$	0			$	0		$	(8	)	$	84		$	29		$	105
	to Level 3 assets and liabilities still held at
	the end of the period included in realized
	investment gains (losses)
	(1) Derivative assets and liabilities are presented net
	(2) Due to a lack of visibility to observe significant inputs to price
	(3) A result of changing our pricing methodology to a valuation method that uses observable market data as significant inputs to estimate fair value
Fair Value Inputs Assets Quantitative Information	The following tables summarize the significant unobservable inputs used in the valuation of our Level 3 available-for-sale investments and derivatives as of December 31. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments.
	2014
	(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
													(Weighted Average)
	Assets:
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Mortgage- and asset-backed securities			$	223				Consensus pricing		Offered quotes		N/A	(d)
	Banks/financial institutions			26					Consensus pricing		Offered quotes		N/A	(d)
	Perpetual securities:
	Banks/financial institutions			149					Consensus pricing		Offered quotes		N/A	(d)
	Equity securities			3					Net asset value		Offered quotes		$1 - $677 ($6)
	Other assets:
	Foreign currency swaps			8					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
											Interest rates (JPY)		.53% - 1.34%	(b)
											CDS spreads		16 - 105 bps
											Foreign exchange rates		20.50%	(c)
				98					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
											Interest rates (JPY)		.53% - 1.34%	(b)
											Foreign exchange rates		20.50%	(c)
	Total assets			$	507
	(a) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
	(b) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
	(c) Based on 10 year volatility of JPY/USD exchange rate
	(d) N/A represents securities where we receive unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
	2013
	(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
													(Weighted Average)
	Assets:
	Securities available for sale, carried at fair value:
	Fixed maturities:
	Mortgage- and asset-backed securities			$	369				Consensus pricing		Offered quotes		N/A	(e)
	Banks/financial institutions			23					Consensus pricing		Offered quotes		N/A	(e)
	Perpetual securities:
	Banks/financial institutions			52					Consensus pricing		Offered quotes		N/A	(e)
	Equity securities			3					Net asset value		Offered quotes		$1-$774 ($7)
	Other assets:
	Foreign currency swaps			30					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											CDS spreads		16 - 141 bps
											Foreign exchange rates		21.16%	(d)
				9					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											CDS spreads		17 - 149 bps
				65					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											Foreign exchange rates		21.16%	(d)
	Credit default swaps			1					Discounted cash flow		Base correlation		65% - 76% (72%)	(a)
											CDS spreads		65 - 106 (92) bps
											Recovery rate		37.00%
	Interest rate swaps			1					Discounted cash flow		Base correlation		65% - 76% (72%)	(a)
											CDS spreads		65 - 106 (92) bps
											Recovery rate		37.00%
	Total assets			$	553
	(a) Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
	(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
	(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
	(d) Based on 10 year volatility of JPY/USD exchange rate
	(e) N/A represents securities where we receive unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
Fair Value Inputs Liabilities Quantitative Information
	2014
	(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
													(Weighted Average)
	Liabilities:
	Foreign currency swaps			$	176				Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
											Interest rates (JPY)		.53% - 1.34%	(b)
											CDS spreads		16 - 105 bps
											Foreign exchange rates		20.50%	(c)
				111					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
											Interest rates (JPY)		.53% - 1.34%	(b)
											CDS spreads		13 - 145 bps
				31					Discounted cash flow		Interest rates (USD)		2.28% - 2.70%	(a)
											Interest rates (JPY)		.53% - 1.34%	(b)
											Foreign exchange rates		20.50%	(c)
	Total liabilities			$	318
	(a) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
	(b) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
	(c) Based on 10 year volatility of JPY/USD exchange rate
	2013
	(In millions)		Fair Value						Valuation Technique(s)		Unobservable Input		Range
													(Weighted Average)
	Liabilities:
	Foreign currency swaps			$	99				Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											CDS spreads		16 - 141 bps
											Foreign exchange rates		21.16%	(d)
				24					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											CDS spreads		11 - 189 bps
				80					Discounted cash flow		Interest rates (USD)		3.09% - 3.96%	(b)
											Interest rates (JPY)		.93% - 2.02%	(c)
											Foreign exchange rates		21.16%	(d)
	Credit default swaps			4					Discounted cash flow		Base correlations		65% - 76% (72%)	(a)
											CDS spreads		65 - 106 (92) bps
											Recovery rate		37.00%
	Total liabilities			$	207
	(a) Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
	(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps
	(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
	(d) Based on 10 year volatility of JPY/USD exchange rate

DEFERRED_POLICY_ACQUISITION_CO1

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES (Tables)	12 Months Ended
	Dec. 31, 2014
Deferred Policy Acquisition Costs and Insurance Expense Disclosure [Abstract]
Schedule of Deferred Policy Acquisition Costs	The following table presents a rollforward of deferred policy acquisition costs by segment for the years ended December 31.
		2014								2013
	(In millions)	Japan				U.S.				Japan				U.S.
	Deferred policy acquisition costs:
	Balance, beginning of year		$	5,819			$	2,979			$	6,801			$	2,857
	Capitalization		790				548				893				555
	Amortization		(649		)		(459		)		(641		)		(433		)
	Foreign currency translation and other		(749		)		(6		)		(1,234		)		0
	Balance, end of year		$	5,211			$	3,062			$	5,819			$	2,979
Advertising Expense	Advertising expense, which is included in insurance expenses in the consolidated statements of earnings, was as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Advertising expense:
	Aflac Japan		$	103			$	112			$	127
	Aflac U.S.		126				128				127
	Total advertising expense		$	229			$	240			$	254
Schedule Of Depreciation And Amortization Expense	Depreciation and other amortization expenses, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Depreciation expense		$	47			$	56			$	60
	Other amortization expense		8				13				7
	Total depreciation and other amortization expense		$	55			$	69			$	67
Schedule of Lease Expenses	Lease and rental expense, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
	(In millions)	2014				2013				2012
	Lease and rental expense:
	Aflac Japan		$	52			$	55			$	71
	Aflac U.S.		15				10				9
	Other		1				1				1
	Total lease and rental expense		$	68			$	66			$	81

POLICY_LIABILITIES_Tables

POLICY LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2014
Policy liabilities [Abstract]
Liability for Future Policy Benefits by Product Segment	The liability for future policy benefits as of December 31 consisted of the following:
				Liability Amounts						Interest Rates
	(In millions)	Policy		2014		2013				Year of			In 20
		Issue Year								Issue			Years
	Health insurance:
	Japan:	2002 - 2014		$	3,900	$	3,370			1.25 - 2.5	%		1.25 - 2.5	%
		1974 - 2013		3,449		3,889				2.7 - 2.75			2.25 - 2.75
		1998 - 2014		10,641		11,763				3			3
		1997 - 1999		2,461		2,842				3.5			3.5
		1994 - 1996		3,023		3,483				4.0 - 4.5			4.0 - 4.5
		1987 - 1994		14,394		16,727				5.5			5.5
		1985 - 1991		1,923		2,262				5.25 - 6.75			5.25 - 5.5
		1978 - 1984		2,260		2,699				6.5			5.5
	U.S.:	2012 - 2014		588		345				3.0 - 3.75			3.0 - 3.75
		2011		276		243				4.75			4.75
		2005 - 2010		2,951		2,897				5.5			5.5
		1988 - 2004		706		725				8			6
		1986 - 2004		1,293		1,301				6			6
		1981 - 1986		183		190				6.5 - 7.0			5.5 - 6.5
		1998 - 2004		1,260		1,237				7			7
		Other		21		22
	Life insurance:
	Japan:	2013 - 2014		312		59				1.5 - 1.75			1.5 - 1.75
		2001 - 2013		3,674		3,009				1.65 - 1.85			1.65 - 1.85
		2011 - 2014		2,298		1,584				2			2
		2009 - 2011		1,890		1,648				2.25			2.25
		2005 - 2011		1,214		1,211				2.5			2.5
		1985 - 2006		2,006		2,303				2.7			2.25
		2007 - 2011		1,010		1,025				2.75			2.75
		1999 - 2011		1,944		2,164				3			3
		1996 - 2009		633		721				3.5			3.5
		1994 - 1996		884		1,021				4.0 - 4.5			4.0 - 4.5
	U.S.:	1956 - 2014		452		396				3.5 - 6.0			3.5 - 6.0
	Total			$	65,646	$	69,136
Schedule of Liability for Unpaid Claims Adjustment Expense	Changes in the liability for unpaid policy claims were as follows for the years ended December 31:
	(In millions)	2014				2013					2012
	Unpaid supplemental health claims, beginning of year		$	3,537			$	3,781				$	3,749
	Less reinsurance recoverables		9				10					0
	Net balance, beginning of year		3,528				3,771					3,749
	Add claims incurred during the year related to:
	Current year		6,866				7,215					8,013
	Prior years		(301		)		(236		)			(173		)
	Total incurred		6,565				6,979					7,840
	Less claims paid during the year on claims incurred during:
	Current year		4,532				4,834					5,453
	Prior years		1,873				1,931					2,082
	Total paid		6,405				6,765					7,535
	Effect of foreign exchange rate changes on unpaid claims		(283		)		(457		)			(283		)
	Net balance, end of year		3,405				3,528					3,771
	Add reinsurance recoverables		7				9					10
	Unpaid supplemental health claims, end of year		3,412				3,537					3,781
	Unpaid life claims, end of year		218				226					253
	Total liability for unpaid policy claims		$	3,630			$	3,763				$	4,034

REINSURANCE_REINSURANCE_Tables

REINSURANCE REINSURANCE (Tables)	12 Months Ended
	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
Effects of Reinsurance	for the years ended December 31.
	(In millions)	2014				2013
	Direct premium income		$	19,412			$	20,233
	Ceded to other companies:
	Ceded Aflac Japan closed medical block		(311		)		(76		)
	Other		(39		)		(34		)
	Assumed from other companies		10				12
	Net premium income		$	19,072			$	20,135
	Direct benefits and claims		$	13,235			$	13,903
	Ceded benefits and change in reserves for future benefits:
	Ceded Aflac Japan closed medical block		(276		)		(67		)
	Other		(27		)		(31		)
	Assumed from other companies		5				8
	Benefits and claims, net		$	12,937			$	13,813

NOTES_PAYABLE_Tables

NOTES PAYABLE (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	A summary of notes payable as of December 31 follows:
	(In millions)	2014				2013
	3.45% senior notes due August 2015		$	300			$	300
	2.65% senior notes due February 2017		653		(1)		655		(1)
	8.50% senior notes due May 2019		850				850
	4.00% senior notes due February 2022		350		(2)		349		(2)
	3.625% senior notes due June 2023		700				700
	3.625% senior notes due November 2024		749		(2)		0
	6.90% senior notes due December 2039		397		(2)		396		(2)
	6.45% senior notes due August 2040		448		(2)		448		(2)
	5.50% subordinated debentures due September 2052		500				500
	Yen-denominated Uridashi notes:
	2.26% notes due September 2016 (principal amount 8 billion yen)		66				76
	Yen-denominated Samurai notes:
	1.47% notes paid July 2014 (principal amount 28.7 billion yen)		0				272
	1.84% notes due July 2016 (principal amount 15.8 billion yen)		131				150
	Variable interest rate notes paid July 2014 (1.30% in 2013, principal amount		0				52
	5.5 billion yen)
	Yen-denominated loans:
	3.60% loan due July 2015 (principal amount 10 billion yen)		83				95
	3.00% loan due August 2015 (principal amount 5 billion yen)		41				48
	Capitalized lease obligations payable through 2019		14				6
	Total notes payable		$	5,282			$	4,897
Schedule of Maturities of Long Term Debt	The aggregate contractual maturities of notes payable during each of the years after December 31, 2014, are as follows:
	(In millions)	Long-term				Capitalized				Total
		Debt				Lease				Notes
						Obligations				Payable
	2015		$	424			$	4			$	428
	2016		197				4				201
	2017		650				3				653
	2018		0				2				2
	2019		850				1				851
	Thereafter		3,150				0				3,150
	Total		$	5,271			$	14			$	5,285

INCOME_TAXES_Tables

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The components of income tax expense (benefit) applicable to pretax earnings for the years ended December 31 were as follows:
	(In millions)	Foreign				U.S.				Total
	2014:00:00
	Current		$	995			$	84			$	1,079
	Deferred		125				336				461
	Total income tax expense		$	1,120			$	420			$	1,540
	2013:00:00
	Current		$	934			$	302			$	1,236
	Deferred		299				123				422
	Total income tax expense		$	1,233			$	425			$	1,658
	2012:00:00
	Current		$	513			$	303			$	816
	Deferred		950				(330		)		620
	Total income tax expense		$	1,463			$	(27	)		$	1,436
Schedule of Effective Income Tax Rate Reconciliation	The principal reasons for the differences and the related tax effects for the years ended December 31 were as follows:
	(In millions)	2014				2013				2012
	Income taxes based on U.S. statutory rates		$	1,572			$	1,685			$	1,506
	Utilization of foreign tax credit		(32		)		(37		)		(53		)
	Nondeductible expenses		5				6				8
	Other, net		(5		)		4				(25		)
	Income tax expense		$	1,540			$	1,658			$	1,436
Schedule of Income Tax Expense Benefit Intraperiod Tax Allocation	Total income tax expense for the years ended December 31 was allocated as follows:
	(In millions)	2014				2013				2012
	Statements of earnings		$	1,540			$	1,658			$	1,436
	Other comprehensive income (loss):
	Unrealized foreign currency translation gains (losses) during period		(419		)		253				363
	Unrealized gains (losses) on investment securities:
	Unrealized holding gains (losses) on investment		2,237				(904		)		904
	securities during period
	Reclassification adjustment for realized (gains) losses		19				19				(174		)
	on investment securities included in net earnings
	Unrealized gains (losses) on derivatives during period		(3		)		(4		)		(8		)
	Pension liability adjustment during period		(31		)		55				(7		)
	Total income tax expense (benefit) related to items of		1,803				(581		)		1,078
	other comprehensive income (loss)
	Additional paid-in capital (exercise of stock options)		(7		)		(8		)		(12		)
	Total income taxes		$	3,336			$	1,069			$	2,502
Schedule of Deferred Tax Assets and Liabilities	The income tax effects of the temporary differences that gave rise to deferred income tax assets and liabilities as of December 31 were as follows:
	(In millions)	2014				2013
	Deferred income tax liabilities:
	Deferred policy acquisition costs		$	2,209			$	2,406
	Unrealized gains on investment securities		2,584				533
	Premiums receivable		139				134
	Policy benefit reserves		1,376				1,451
	Depreciation		51				54
	Other		20				22
	Total deferred income tax liabilities		6,379				4,600
	Deferred income tax assets:
	Other basis differences in investment securities		1,331				1,129
	Unfunded retirement benefits		16				16
	Other accrued expenses		4				23
	Policy and contract claims		99				111
	Foreign currency loss on Japan branch		327				189
	Deferred compensation		226				182
	Capital loss carryforwards		26				514
	Total deferred income tax assets		2,029				2,164
	Net deferred income tax liability		4,350				2,436
	Current income tax liability		943				1,282
	Total income tax liability		$	5,293			$	3,718
Summary of Income Tax Contingencies	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows for the years ended December 31:
	(In millions)		2014			2013
	Balance, beginning of year		$	328		$	401
	Additions for tax positions of prior years		2			1
	Reductions for tax positions of prior years		(21		)	(74		)
	Balance, end of year		$	309		$	328

SHAREHOLDERS_EQUITY_Tables

SHAREHOLDERS' EQUITY (Tables)	12 Months Ended
	Dec. 31, 2014
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 years ended December 31.
	(In thousands of shares)	2014		2013		2012
	Common stock - issued:
	Balance, beginning of period	667,046		665,239		663,639
	Exercise of stock options and issuance of restricted shares	1,086		1,807		1,600
	Balance, end of period	668,132		667,046		665,239
	Treasury stock:
	Balance, beginning of period	207,633		197,453		197,329
	Purchases of treasury stock:
	Open market	19,660		13,212		1,948
	Other	157		222		360
	Dispositions of treasury stock:
	Shares issued to AFL Stock Plan	-1,251		-1,365		-1,670
	Exercise of stock options	-391		-1,734		-387
	Other	-121		-155		-127
	Balance, end of period	225,687		207,633		197,453
	Shares outstanding, end of period	442,445		459,413		467,786
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 at December 31:
	(In thousands)	2014					2013					2012
	Anti-dilutive share-based awards		1,215					2,198					5,880
Schedule of Weighted Average Number of Shares	The weighted-average shares used in calculating earnings per share for the years ended December 31 were as follows:
	(In thousands of shares)	2014			2013			2012
	Weighted-average outstanding shares used for calculating basic EPS	451,204			464,502			466,868
	Dilutive effect of share-based awards	2,796			2,906			2,419
	Weighted-average outstanding shares used for calculating diluted EPS	454,000			467,408			469,287
Changes in Accumulated Other Comprehensive Income (Detail)	The table below is a reconciliation of accumulated other comprehensive income by component for the years ended December 31.
	Changes in Accumulated Other Comprehensive Income
	2014
	(In millions)	Unrealized Foreign						Unrealized						Unrealized				Pension				Total
		Currency Translation						Gains (Losses)						Gains (Losses)				Liability
		Gains (Losses)						on Investment Securities						on Derivatives				Adjustment
	Balance, beginning of period		$	(1,505	)				$	1,035					$	(12	)		$	(81	)		$	(563	)
	Other comprehensive		(1,036		)				3,672						(14		)		(44		)		2,578
	income before
	reclassification
	Amounts reclassified from		0						(35		)				0				(1		)		(36		)
	accumulated other
	comprehensive income
	Net current-period other		(1,036		)				3,637						(14		)		(45		)		2,542
	comprehensive
	income
	Balance, end of period		$	(2,541	)				$	4,672					$	(26	)		$	(126	)		$	1,979
	All amounts in the table above are net of tax.
	2013
	(In millions)	Unrealized Foreign						Unrealized						Unrealized				Pension Liability Adjustment				Total
		Currency Translation						Gains (Losses)						Gains (Losses)
		Gains (Losses)						on Investment Securities						on Derivatives
	Balance, beginning of period		$	333					$	2,570					$	(5	)		$	(183	)		$	2,715
	Other comprehensive		(1,833		)				(1,499		)				(7		)		92				(3,247		)
	income before
	reclassification
	Amounts reclassified from		(5		)				(36		)				0				10				(31		)
	accumulated other
	comprehensive income
	Net current-period other		(1,838		)				(1,535		)				(7		)		102				(3,278		)
	comprehensive
	income
	Balance, end of period		$	(1,505	)				$	1,035					$	(12	)		$	(81	)		$	(563	)
	All amounts in the table above are net of tax.
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	The table below summarizes the amounts reclassified from each component of accumulated other comprehensive income based on source for the years ended December 31.
	Reclassifications Out of Accumulated Other Comprehensive Income
	(In millions)	2014
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income					Affected Line Item in the
							Statements of Earnings
	Unrealized gains (losses) on available-for-sale		$	57			Sales and redemptions
	securities
			(3		)		Other-than-temporary impairment
							losses realized
			54				Total before tax
			(19		)		Tax (expense) or benefit(1)
			$	35			Net of tax
	Amortization of defined benefit pension items:
	Actuarial gains (losses)		$	(15	)		Acquisition and operating expenses(2)
	Prior service (cost) credit		17				Acquisition and operating expenses(2)
			(1		)		Tax (expense) or benefit(1)
			$	1			Net of tax
	Total reclassifications for the period		$	36			Net of tax
	(1) Based on 35% tax rate
	(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see
	Note 14 for additional details).
	(In millions)	2013
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income					Affected Line Item in the
							Statements of Earnings
	Unrealized foreign currency translation gains		$	7			Sales and redemptions
	(losses)
			(2		)		Tax (expense) or benefit(1)
			$	5			Net of tax
	Unrealized gains (losses) on available-for-sale		$	255			Sales and redemptions
	securities
			(199		)		Other-than-temporary impairment
							losses realized
			56				Total before tax
			(20		)		Tax (expense) or benefit(1)
			$	36			Net of tax
	Amortization of defined benefit pension items:
	Actuarial gains (losses)		$	(19	)		Acquisition and operating expenses(2)
	Prior service (cost) credit		4				Acquisition and operating expenses(2)
			5				Tax (expense) or benefit(1)
			$	(10	)		Net of tax
	Total reclassifications for the period		$	31			Net of tax
	(1) Based on 35% tax rate
	(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see
	Note 14 for additional details).

SHAREBASED_COMPENSATION_Tables

SHARE-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Expense Recognized in Connection with Share Based Awards	The following table presents the impact of the expense recognized in connection with share-based awards for the periods ended December 31.
	(In millions, except for per-share amounts)	2014						2013						2012
	Impact on earnings from continuing operations		$	41					$	37					$	37
	Impact on earnings before income taxes		41						37						37
	Impact on net earnings		28						25						26
	Impact on net earnings per share:
	Basic		$	0.06					$	0.05					$	0.06
	Diluted		0.06						0.05						0.06
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following table presents the assumptions used in valuing options granted during the years ended December 31.
		2014				2013				2012
	Expected term (years)		6.3				6.6				6.5
	Expected volatility		30	%			34	%			38	%
	Annual forfeiture rate		2.7				1.6				1.6
	Risk-free interest rate		2.8				1.8				2.1
	Dividend yield		2.3				2.6				1.3
Schedule of Share-based Compensation, Stock Options, Activity	The following table summarizes stock option activity.
	(In thousands of shares)	Stock					Weighted-Average
		Option					Exercise Price
		Shares					Per Share
	Outstanding at December 31, 2011		14,563					$	42.76
	Granted in 2012		784					47.25
	Canceled in 2012		(134	)				48.59
	Exercised in 2012		(2,476	)				32.27
	Outstanding at December 31, 2012		12,737					45
	Granted in 2013		703					52.86
	Canceled in 2013		(179	)				44.79
	Exercised in 2013		(3,281	)				40.52
	Outstanding at December 31, 2013		9,980					47.03
	Granted in 2014		678					61.81
	Canceled in 2014		(115	)				52.01
	Exercised in 2014		(1,236	)				41.04
	Outstanding at December 31, 2014		9,307					$	48.84
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable
	(In thousands of shares)	2014					2013					2012
	Shares exercisable, end of year		7,497					8,042					10,635
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range	The following table summarizes information about stock options outstanding and exercisable at December 31, 2014.
	(In thousands of shares)										Options Outstanding										Options Exercisable
		Range of									Stock Option					Wgtd.-Avg.		Wgtd.-Avg.			Stock Option		Wgtd.-Avg.
		Exercise Prices									Shares					Remaining		Exercise			Shares		Exercise
		Per Share									Outstanding					Contractual		Price			Exercisable		Price
																Life (Yrs.)		Per Share					Per Share
		$	14.99		-	$	43.07					2,028					3.8		$	34.46		1,945		$	34.2
		43.28			-	47.25						2,144					3.1		45.93			2,046		45.93
		47.33			-	51.91						1,883					5.4		48.97			1,109		48.86
		52.14			-	61.81						2,479					4.5		58.65			2,296		58.79
		61.84			-	67.67						773					8.5		62.85			101		64.63
		$	14.99		-	$	67.67					9,307					4.5		$	48.84		7,497		$	47.51
Schedule of Cash Proceeds Received from Share-based Payment Awards	The following table summarizes stock option activity during the years ended December 31.
	(In millions)	2014						2013						2012
	Total intrinsic value of options exercised		$	25					$	66					$	41
	Cash received from options exercised		39						113						35
	Tax benefit realized as a result of options exercised and		17						30						24
	restricted stock releases
Schedule of Nonvested Restricted Stock Units Activity	The value of restricted stock awards is based on the fair market value of our common stock at the date of grant. The following table summarizes restricted stock activity during the years ended December 31.
	(In thousands of shares)	Shares					Weighted-Average
							Grant-Date
							Fair Value
							Per  Share
	Restricted stock at December 31, 2011		1,350					$	40.92
	Granted in 2012		637					48.18
	Canceled in 2012		(56	)				48.22
	Vested in 2012		(568	)				26.13
	Restricted stock at December 31, 2012		1,363					50.19
	Granted in 2013		782					52.77
	Canceled in 2013		(56	)				48.63
	Vested in 2013		(418	)				47.49
	Restricted stock at December 31, 2013		1,671					52.12
	Granted in 2014		584					62.12
	Canceled in 2014		(27	)				52.66
	Vested in 2014		(348	)				56.95
	Restricted stock at December 31, 2014		1,880					$	54.33

STATUTORY_ACCOUNTING_AND_DIVID1

STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS (Tables)	12 Months Ended
	Dec. 31, 2014
Statutory Accounting Practices Disclosure [Abstract]
Reconciliation of Capital and Surplus between NAIC and Nebraska state basis	A reconciliation of Aflac's capital and surplus between SAP and practices permitted by the state of Nebraska is shown below:
	(In millions)	2014				2013
	Capital and surplus, Nebraska state basis		$	10,839			$	9,630
	State Permitted Practice:
	Refundable lease deposits – Japan		(36		)		(41		)
	Separate Account Funding Agreements		0				35
	Capital and surplus, NAIC basis		$	10,803			$	9,624
Profits Repatriated Disclosure	Profits repatriated by Aflac Japan to Aflac U.S. were as follows for the years ended December 31:
		In Dollars											In Yen
	(In millions of dollars and billions of yen)	2014				2013				2012			2014		2013		2012
	Profit repatriation		$	1,704			$	771			$	422		181.4		76.8		33.1

BENEFIT_PLANS_Tables

BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 31, 2014
Schedule of Net Funded Status	Information with respect to our benefit plans' assets and obligations as of December 31 was as follows:
			Pension Benefits																						Other
			Japan											U.S.											Postretirement Benefits
	(In millions)		2014					2013						2014					2013						2014					2013
	Projected benefit obligation:
	Benefit obligation, beginning of year			$	270				$	313					$	601				$	613					$	46				$	98
	Service cost			15					16						20					22						1					5
	Interest cost			9					10						38					23						2					3
	Plan amendments			0					0						0					(4		)				0					(51		)
	Actuarial (gain) loss			21					(3		)				74					(37		)				(3		)			(7		)
	Benefits and expenses paid			(9		)			(8		)				(16		)			(16		)				(2		)			(2		)
	Effect of foreign exchange			(39		)			(58		)				0					0						0					0
	rate changes
	Benefit obligation, end of year			267					270						717					601						44					46
	Plan assets:
	Fair value of plan assets,			182					187						313					261						0					0
	beginning of year
	Actual return on plan assets			12					13						26					39						0					0
	Employer contributions			24					26						18					29						2					2
	Benefits and expenses paid			(9		)			(8		)				(16		)			(16		)				(2		)			(2		)
	Effect of foreign exchange			(26		)			(36		)				0					0						0					0
	rate changes
	Fair value of plan assets, end of year			183					182						341					313						0					0
	Funded status of the plans(1)			$	(84	)			$	(88	)				$	(376	)			$	(288	)				$	(44	)			$	(46	)
	Amounts recognized in accumulated other
	comprehensive income:
	Net actuarial (gain) loss			$	40				$	33					$	167				$	111					$	19				$	25
	Prior service (credit) cost			(2		)			(2		)				(4		)			(4		)				(28		)			(45		)
	Transition obligation			0					1						0					0						0					0
	Total included in accumulated			$	38				$	32					$	163				$	107					$	(9	)			$	(20	)
	other comprehensive income
	Accumulated benefit obligation			$	235				$	239					$	611				$	514					N/A			(2)		N/A			(2)
	(1) Recognized in other liabilities in the consolidated balance sheets
	(2) Not applicable
Schedule of Assumptions Used
		Pension Benefits																				Other
		Japan										U.S.										Postretirement Benefits
		2014			2013			2012				2014			2013			2012				2014			2013			2012
	Weighted-average actuarial assumptions:
	Discount rate - net periodic benefit cost	2.25	%		2.25	%		2.25	%			4.75	%		4.25	%		4.75	%			4.75	%		4.25	%		4.75	%
	Discount rate - benefit obligations	1.75			2.25			2.25				4.5			4.75			4.25				4.5			4.75			4.25
	Expected long-term return on plan assets	2			2			2.5				7.5			7.5			7.5				N/A		(1)	N/A		(1)	N/A		(1)
	Rate of compensation increase	N/A		(1)	N/A		(1)	N/A		(1)		4			4			4				N/A		(1)	N/A		(1)	N/A		(1)
	Health care cost trend rates	N/A		(1)	N/A		(1)	N/A		(1)		N/A		(1)	N/A		(1)	N/A		(1)		5.7		(2)	6.4		(2)	5.7		(2)
	(1) Not applicable
	(2)For the years 2014, 2013 and 2012, the health care cost trend rates are expected to trend down to 4.6% in 78 years, 4.6% in
	78 years, and 4.7% in 79 years, respectively.
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates	A one-percentage point increase and decrease in assumed health care cost trend rates would have the following effects as of December 31, 2014:
	(In millions)
	One percentage point increase:
	Increase in total service and interest costs			$	0
	Increase in postretirement benefit obligation			3
	One percentage point decrease:
	Decrease in total service and interest costs			$	0
	Decrease in postretirement benefit obligation			2
Schedule of Net Benefit Costs	Pension and other postretirement benefit expenses, included in acquisition and operating expenses in the consolidated statements of earnings for the years ended December 31, included the following components:
			Pension Benefits																																		Other
				Japan																	U.S.																Postretirement Benefits
	(In millions)		2014						2013						2012						2014						2013						2012				2014				2013				2012
	Service cost			$	15					$	16					$	18					$	20					$	22					$	18			$	1			$	5			$	6
	Interest cost			9						10						7						38						23						24				2				3				4
	Expected return on plan			(4		)				(3		)				(4		)				(20		)				(17		)				(16		)		0				0				0
	assets
	Amortization of net actuarial			1						2						3						11						15						11				3				2				1
	loss
	Amortization of prior service			0						0						0						0						0						0				(17		)		(4		)		0
	cost (credit)
	Net periodic (benefit) cost			$	21					$	25					$	24					$	49					$	43					$	37			$	(11	)		$	6			$	11
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	The following table summarizes the amounts recognized in other comprehensive loss (income) for the years ended December 31:
			Pension Benefits																																		Other
			Japan																		U.S.																Postretirement Benefits
	(In millions)		2014						2013						2012						2014						2013						2012				2014				2013				2012
	Net actuarial loss (gain)			$	12					$	(14	)				$	(10	)				$	67					$	(59	)				$	45			$	(3	)		$	(7	)		$	5
	Amortization of net actuarial loss			(1		)				(2		)				(3		)				(11		)				(15		)				(11		)		(3		)		(2		)		(1		)
	Prior service cost (credit)			0						0						0						0						(4		)				(1		)		0				(51		)		2
	Amortization of prior			0						0						0						0						0						0				17				4				0
	service cost
	Total			$	11					$	(16	)				$	(13	)				$	56					$	(78	)				$	33			$	11			$	(56	)		$	6
Schedule of Expected Benefit Payments	The following table provides expected benefit payments, which reflect expected future service, as appropriate.
			Pension Benefits											Other
	(In millions)		Japan					U.S.						Postretirement Benefits
	2015			$	7				$	20					$	2
	2016			11					21						2
	2017			8					28						3
	2018			7					26						3
	2019			9					27						4
	2020-2024			63					159						22
Schedule of Allocation of Plan Assets	Asset allocation targets as of December 31, 2014 were as follows:
			Japan Pension					U.S. Pension
	Domestic equities			0	%				40	%
	International equities			15					20
	Fixed income securities			70					40
	Other			15					0
	Total			100	%				100	%
Plan Assets
Fair Value, Assets Measured on Recurring Basis	The following table presents the fair value of Aflac Japan's pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 2 in the fair value hierarchy, except cash and cash equivalents which are classified as Level 1.
	(In millions)	2014						2013
	Japan pension plan assets:
	International equity securities		$	34					$	34
	Fixed income securities:
	Japanese bonds		72						60
	International bonds		44						43
	Mutual funds		0						21
	Insurance contracts		22						24
	Cash and cash equivalents		11						0
	Total		$	183					$	182
	The following table presents the fair value of Aflac U.S.'s pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 1 in the fair value hierarchy.
	(In millions)	2014						2013
	U.S. pension plan assets:
	Mutual funds:
	Large cap equity funds		$	116					$	110
	Mid cap equity funds		14						19
	Real estate equity funds		10						9
	International equity funds		61						68
	Fixed income bond funds		136						103
	Aflac Incorporated common stock		4						4
	Total		$	341					$	313

COMMITMENTS_AND_CONTINGENT_LIA1

COMMITMENTS AND CONTINGENT LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	Future minimum lease payments due under non-cancelable operating leases at December 31, 2014, were as follows:
	(In millions)
	2015	$	55
	2016	29
	2017	19
	2018	11
	2019	7
	Thereafter	8
	Total future minimum lease payments	$	129

Recovered_Sheet1

Unaudited Consolidated Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure Unaudited Consolidated Quarterly Financial Data [Abstract]
Schedule of Quarterly Financial Information	In management's opinion, the following quarterly financial information fairly presents the results of operations for such periods and is prepared on a basis consistent with our annual audited financial statements.
	(In millions, except for per-share amounts)	March 31,				June 30,			September 30,			December 31,
		2014				2014			2014			2014
	Net premium income		$	4,854			$	4,888		$	4,841		$	4,489
	Net investment income		827				843			841			808
	Realized investment gains (losses)		(46		)		102			16			143
	Other income		5				5			38			74
	Total revenues		5,640				5,838			5,736			5,514
	Total benefits and expenses		4,536				4,600			4,662			4,439
	Earnings before income taxes		1,104				1,238			1,074			1,075
	Total income tax		372				428			368			372
	Net earnings		$	732			$	810		$	706		$	703
	Net earnings per basic share		$	1.61			$	1.79		$	1.56		$	1.57
	Net earnings per diluted share		1.6				1.78			1.56			1.57
	Quarterly amounts may not agree in total to the corresponding annual amounts due to rounding.
	(In millions, except for per-share amounts)	March 31,				June 30,			September 30,			December 31,
		2013				2013			2013			2013
	Net premium income		$	5,184			$	5,013		$	5,028		$	4,910
	Net investment income		833				813			821			826
	Realized investment gains (losses)		156				201			22			20
	Other income		35				17			15			45
	Total revenues		6,208				6,044			5,886			5,801
	Total benefits and expenses		4,847				4,686			4,817			4,773
	Earnings before income taxes		1,361				1,358			1,069			1,028
	Total income tax		469				469			367			353
	Net earnings		$	892			$	889		$	702		$	675
	Net earnings per basic share		$	1.91			$	1.91		$	1.51		$	1.46
	Net earnings per diluted share		1.9				1.9			1.5			1.45
	Quarterly amounts may not agree in total to the corresponding annual amounts due to rounding.

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Summary of Signficant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Significant Accounting Policies [Line Items]
Income tax expense (benefit) related to items of other comprehensive income (loss)	$1,803	($581)	$1,078
Accounting Standards Update 2010-26
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				-458
Aflac Japan
Significant Accounting Policies [Line Items]
Aflac Japan's percentage of the Company's total revenues	72.00%	74.00%	77.00%
Percentage of the Company assets	82.00%	85.00%
Retained earnings: | Accounting Standards Update 2010-26
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				-391
Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2010-26
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				-67
Dollar denominated investment portfolio | Aflac Japan
Significant Accounting Policies [Line Items]
Income tax expense (benefit) related to items of other comprehensive income (loss)		$614	$492
Effective income tax rate excluding income tax expense (benefit) related to Aflac Japan's dollar-denominated portfolio		31.00%	32.00%

BUSINESS_SEGMENT_AND_FOREIGN_I2

BUSINESS SEGMENT AND FOREIGN INFORMATION - Additional Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
	segment
Segment Reporting Information [Line Items]
Reportable insurance business segments	2
Total receivables related to Aflac Japan's operations	$842	$1,165
Aflac Japan
Segment Reporting Information [Line Items]
Total receivables related to Aflac Japan's operations	$386	$731
Percentage of total receivables related to Aflac Japan's operations	45.80%	82.90%
Maximum | Machinery and Equipment [Member]
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Useful Life	20 years
Maximum | Building
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Useful Life	50 years
Maximum | Furniture and fixtures
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Useful Life	20 years

BUSINESS_SEGMENT_AND_FOREIGN_I3

BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Revenues (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums	$4,489	$4,841	$4,888	$4,854	$4,910	$5,028	$5,013	$5,184	$19,072		$20,135		$22,148
Net investment income	808	841	843	827	826	821	813	833	3,319		3,293		3,473
Other income	74	38	5	5	45	15	17	35	122		112		92
Total revenues	5,514	5,736	5,838	5,640	5,801	5,886	6,044	6,208	22,728		23,939		25,364
Realized investment gains (losses), non-operating									171	[1]	389	[1]	-349
Other non-operating income (loss)									67		28		-7
Gain (loss) on change in fair value of derivative, interest rate component, operating									44		10
Aflac Japan
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									13,861		14,982		17,151
Net investment income									2,662		2,651		2,845
Other income									32		55		57
Total revenues									16,555		17,688		20,053
Aflac Japan | Cancer
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									5,596		6,123		7,537
Aflac Japan | Medical and other health
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									3,770		4,282		5,244
Aflac Japan | Life insurance
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									4,495		4,577		4,370
Aflac U.S.
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									5,211		5,153		4,996
Net investment income									645		632		613
Other income									3		6		19
Total revenues									5,859		5,791		5,628
Aflac U.S. | Cancer
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									1,279		1,283		1,282
Aflac U.S. | Life insurance
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									258		252		242
Aflac U.S. | Accident and disability
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									2,303		2,284		2,213
Aflac U.S. | Other health
Segment Reporting, Revenue Reconciling Item [Line Items]
Net earned premiums									1,371		1,334		1,259
Other business segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues									43		49		46
Total Business Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues									22,457		23,528		25,727
Corporate
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues									281		302		269
Intercompany eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues									($248)		($308)		($276)
[1]	Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations

BUSINESS_SEGMENT_AND_FOREIGN_I4

BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Pretax Earnings (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									$4,253		$4,399		$4,658
Realized investment gains (losses), non-operating									171	[1]	389	[1]	-349
Other non-operating income (loss)									67		28		-7
Earnings before income taxes	1,075	1,074	1,238	1,104	1,028	1,069	1,358	1,361	4,491		4,816		4,302
Income taxes applicable to pretax operating earnings									1,456		1,512		1,561
Effect of foreign currency translation on operating earnings									-117		-357		8
Gain (loss) on change in fair value of derivative, interest rate component, operating									44		10
Aflac Japan
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									3,458		3,628		3,904
Aflac U.S.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									1,073		1,038		997
Other business segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									-2		-1		-3
Total Business Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									4,529		4,665		4,898
Interest expense, noninsurance operations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									-198		-198		-184
Corporate and eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Pretax operating earnings									($78)		($68)		($56)
[1]	Excluding a gain of $44 in 2014 and $10 in 2013 related to the interest rate component of the change in fair value of foreign currency swaps on notes payable which is classified as an operating gain when analyzing segment operations

BUSINESS_SEGMENT_AND_FOREIGN_I5

BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$119,767	$121,307	$131,094
Aflac Japan
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	98,525	102,973	113,678
Aflac U.S.
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	18,383	16,112	16,122
Other business segments
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	128	155	154
Total Business Segments
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	117,036	119,240	129,954
Corporate
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	24,636	19,909	20,318
Intercompany eliminations
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	($21,905)	($17,842)	($19,178)

BUSINESS_SEGMENT_AND_FOREIGN_I6

BUSINESS SEGMENT AND FOREIGN INFORMATION - Yen/Dollar Exchange Rates Used (Detail)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
	USD ($)	JPY (¥)	USD ($)	JPY (¥)	USD ($)	JPY (¥)	Exchange effect on total assets	Exchange effect on total assets	Exchange effect on total liabilities	Exchange effect on total liabilities
							USD ($)	USD ($)	USD ($)	USD ($)
Segment Reporting, Other Significant Reconciling Item [Line Items]
Weighted-average yen/dollar exchange rate		105.46		97.54		79.81
Yen percent strengthening (weakening)	-7.50%	-7.50%	-18.20%	-18.20%	-0.10%	-0.10%
Exchange effect on pretax operating earnings (in millions)	($180)		($534)		$11
Yen/dollar exchange rate at December 31		120.55		105.39
Yen percent strengthening (weakening)	-12.60%	-12.60%	-17.80%	-17.80%
Exchange effect							($10,706)	($17,836)	($12,025)	($19,806)

BUSINESS_SEGMENT_AND_FOREIGN_I7

BUSINESS SEGMENT AND FOREIGN INFORMATION - Information on Transfers of Funds from Aflac Japan (Detail)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012
	USD ($)	JPY (¥)	USD ($)	JPY (¥)	USD ($)	JPY (¥)
Segment Reporting [Abstract]
Management fees	$39		$37		$30
Allocated expenses	71		74		58
Profit repatriation	1,704	181,400	771	76,800	422	33,100
Total transfers from Aflac Japan	$1,814		$882		$510

BUSINESS_SEGMENT_AND_FOREIGN_I8

BUSINESS SEGMENT AND FOREIGN INFORMATION - Classes of Property and Equipment (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Property and equipment:
Land	$168	$168
Buildings	393	444
Equipment	305	329
Total property and equipment	866	941
Less accumulated depreciation	437	460
Net property and equipment	$429	$481

INVESTMENTS_Components_of_Net_

INVESTMENTS - Components of Net Investment Income (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									$3,399	$3,371	$3,520
Less investment expenses									80	78	47
Net investment income	808	841	843	827	826	821	813	833	3,319	3,293	3,473
Fixed Maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									3,249	3,210	3,248
Perpetual securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									141	153	253
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									7	7	17
Short Term Investments and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									$2	$1	$2

INVESTMENTS_AvailableForSale_I

INVESTMENTS - Available-For-Sale Investments in Debt Securities, Perpetual Securities and Equity Securities (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$60,844	$59,515
Gross Unrealized Gains	8,136	3,659
Gross Unrealized Losses	710	2,136
Fair Value	68,270	61,038
Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	58,385	56,511
Gross Unrealized Gains	7,806	3,468
Gross Unrealized Losses	618	1,909
Fair Value	65,573	58,070
Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,440	2,987
Gross Unrealized Gains	321	186
Gross Unrealized Losses	92	226
Fair Value	2,669	2,947
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	19	17
Gross Unrealized Gains	9	5
Gross Unrealized Losses	0	1
Fair Value	28	21
Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	26,501	25,488
Gross Unrealized Gains	3,029	1,016
Gross Unrealized Losses	242	506
Fair Value	29,288	25,998
Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	31,884	31,023
Gross Unrealized Gains	4,777	2,452
Gross Unrealized Losses	376	1,403
Fair Value	36,285	32,072
Japan government and agencies | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	17,341	14,936
Gross Unrealized Gains	1,740	431
Gross Unrealized Losses	0	33
Fair Value	19,081	15,334
Mortgage- and asset-backed securities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	602	771
Mortgage- and asset-backed securities | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	351	558
Gross Unrealized Gains	35	29
Gross Unrealized Losses	0	0
Fair Value	386	587
Mortgage- and asset-backed securities | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	185	163
Gross Unrealized Gains	31	21
Gross Unrealized Losses	0	0
Fair Value	216	184
Public utilities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	7,897	7,562
Public utilities | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	1,691	2,261
Gross Unrealized Gains	226	100
Gross Unrealized Losses	5	18
Fair Value	1,912	2,343
Public utilities | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	5,061	4,931
Gross Unrealized Gains	960	471
Gross Unrealized Losses	36	183
Fair Value	5,985	5,219
Sovereign and supranational | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	1,416	1,523
Sovereign and supranational | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	799	978
Gross Unrealized Gains	163	85
Gross Unrealized Losses	0	28
Fair Value	962	1,035
Sovereign and supranational | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	343	404
Gross Unrealized Gains	111	85
Gross Unrealized Losses	0	1
Fair Value	454	488
Banks/financial Institutions | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	6,598	6,509
Banks/financial Institutions | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	2,438	2,738
Banks/financial Institutions | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,752	2,799
Gross Unrealized Gains	325	220
Gross Unrealized Losses	189	242
Fair Value	2,888	2,777
Banks/financial Institutions | Yen-denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,132	2,582
Gross Unrealized Gains	223	151
Gross Unrealized Losses	92	217
Fair Value	2,263	2,516
Banks/financial Institutions | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,943	3,318
Gross Unrealized Gains	775	447
Gross Unrealized Losses	8	33
Fair Value	3,710	3,732
Banks/financial Institutions | Dollar-denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	125	196
Gross Unrealized Gains	50	35
Gross Unrealized Losses	0	9
Fair Value	175	222
Other corporate | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	28,605	25,222
Other corporate | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	231	209
Other corporate | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,479	3,956
Gross Unrealized Gains	531	151
Gross Unrealized Losses	48	185
Fair Value	3,962	3,922
Other corporate | Yen-denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	183	209
Gross Unrealized Gains	48	0
Gross Unrealized Losses	0	0
Fair Value	231	209
Other corporate | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	22,291	21,123
Gross Unrealized Gains	2,682	1,347
Gross Unrealized Losses	330	1,170
Fair Value	24,643	21,300
U.S. Government and Agencies | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	100	92
Gross Unrealized Gains	17	10
Gross Unrealized Losses	0	4
Fair Value	117	98
Municipalities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	1,257	1,051
Municipalities | Yen-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	88
Gross Unrealized Gains	9
Gross Unrealized Losses	0
Fair Value	97
Municipalities | Dollar-denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	961	992
Gross Unrealized Gains	201	71
Gross Unrealized Losses	2	12
Fair Value	$1,160	$1,051

INVESTMENTS_HeldtoMaturity_Inv

INVESTMENTS - Held-to-Maturity Investments in Debt Securities (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$34,242	$44,415
Gross Unrealized Gains	4,379	2,041
Gross Unrealized Losses	124	610
Fair Value	38,497	45,846
Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	34,242	44,415
Fair Value	38,497	45,846
Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	34,242
Gross Unrealized Gains	4,379	2,041
Gross Unrealized Losses	124	610
Fair Value	38,497	45,846
Japan government and agencies | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	20,023	27,362
Fair Value	23,218	28,708
Japan government and agencies | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	20,023
Gross Unrealized Gains	3,195	1,347
Gross Unrealized Losses	0	1
Fair Value	23,218	28,708
Municipalities | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	346	399
Fair Value	417	440
Municipalities | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	346
Gross Unrealized Gains	71	41
Gross Unrealized Losses	0	0
Fair Value	417	440
Mortgage- and asset-backed securities | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	43	58
Fair Value	46	61
Mortgage- and asset-backed securities | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	43
Gross Unrealized Gains	3	3
Gross Unrealized Losses	0	0
Fair Value	46	61
Public utilities | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	3,342	3,900
Fair Value	3,603	3,928
Public utilities | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	3,342
Gross Unrealized Gains	281	150
Gross Unrealized Losses	20	122
Fair Value	3,603	3,928
Sovereign and supranational | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	2,556	2,941
Fair Value	2,814	3,040
Sovereign and supranational | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	2,556
Gross Unrealized Gains	272	171
Gross Unrealized Losses	14	72
Fair Value	2,814	3,040
Banks/financial Institutions | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	4,932	6,310
Fair Value	5,085	6,128
Banks/financial Institutions | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	4,932
Gross Unrealized Gains	231	146
Gross Unrealized Losses	78	328
Fair Value	5,085	6,128
Other corporate | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	3,000	3,445
Fair Value	3,314	3,541
Other corporate | Yen-denominated | Fixed Maturities
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, fixed maturities, amortized cost	3,000
Gross Unrealized Gains	326	183
Gross Unrealized Losses	12	87
Fair Value	$3,314	$3,541

INVESTMENTS_Additional_Informa

INVESTMENTS - Additional Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	investment	investment	investment
Schedule of Investments [Line Items]
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, number of investments	3	2	7
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, amortized cost	$424	$492	$1,200
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, aggregate unrealized gain (loss)	-54	-153	-290
Unrealized Gain (Loss)	7,426	1,523
Percentage that the lending policy requires that the fair value of the securities and/or unrestricted cash received as collateral be of the fair value of the loaned securities	102.00%
Fair value of debt securities on deposit with regulatory authorities in the United States and Japan	13
Variable Interest Entity, Not Consolidated
Schedule of Investments [Line Items]
Securities available for sale, fixed maturities, amortized cost	6,104	6,724
Securities available for sale, fixed maturities, fair value	6,937	6,916
Number of issuers of VIEs not-consolidated	191
Perpetual securities
Schedule of Investments [Line Items]
Unrealized Gain (Loss)	229	-40
Parent Company
Schedule of Investments [Line Items]
Securities available for sale, fixed maturities, amortized cost	419	322
Securities available for sale, fixed maturities, fair value	$437	$332

INVESTMENTS_Contractual_Maturi

INVESTMENTS - Contractual Maturities of Investments in Fixed Maturities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Held to maturity:
Total fixed maturities held to maturity, amortized cost	$34,242	$44,415
Held to maturity:
Total fixed maturities held to maturity, fair value	38,497	45,846
Aflac Japan
Available for sale:
Due in one year or less	369
Due after one year through five years	1,519
Due after five years through 10 years	10,351
Due after 10 years	34,018
Mortgage- and asset-backed securities	405
Total fixed maturities available for sale, amortized cost	46,662
Held to maturity:
Due after one year through five years	1,520
Due after five years through 10 years	1,937
Due after 10 years	30,742
Mortgage- and asset-backed securities	43
Total fixed maturities held to maturity, amortized cost	34,242
Available for sale:
Due in one year or less	390
Due after one year through five years	1,771
Due after five years through 10 years	10,979
Due after 10 years	38,595
Mortgage- and asset-backed securities	461
Total fixed maturities available for sale, fair value	52,196
Held to maturity:
Due after one year through five years	1,631
Due after five years through 10 years	2,130
Due after 10 years	34,690
Mortgage- and asset-backed securities	46
Total fixed maturities held to maturity, fair value	38,497
Aflac U.S.
Available for sale:
Due in one year or less	65
Due after one year through five years	628
Due after five years through 10 years	1,472
Due after 10 years	9,103
Mortgage- and asset-backed securities	36
Total fixed maturities available for sale, amortized cost	11,304
Held to maturity:
Due after one year through five years	0
Due after five years through 10 years	0
Due after 10 years	0
Mortgage- and asset-backed securities	0
Total fixed maturities held to maturity, amortized cost	0
Available for sale:
Due in one year or less	69
Due after one year through five years	724
Due after five years through 10 years	1,561
Due after 10 years	10,540
Mortgage- and asset-backed securities	46
Total fixed maturities available for sale, fair value	12,940
Held to maturity:
Due after one year through five years	0
Due after five years through 10 years	0
Due after 10 years	0
Mortgage- and asset-backed securities	0
Total fixed maturities held to maturity, fair value	$0

INVESTMENTS_Economic_Maturitie

INVESTMENTS - Economic Maturities of Investments in Perpetual Securities (Detail) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Aflac Japan
Investments Classified by Economic Maturity Date [Line Items]
Due in one year or less	$306
Due after one year through five years	624
Due after 10 years	1,466
Total perpetual securities available for sale	2,396
Due in one year or less	300
Due after one year through five years	674
Due after 10 years	1,635
Total perpetual securities available for sale	2,609
Aflac U.S.
Investments Classified by Economic Maturity Date [Line Items]
Due in one year or less	5
Due after one year through five years	0
Due after 10 years	39
Total perpetual securities available for sale	44
Due in one year or less	5
Due after one year through five years	0
Due after 10 years	55
Total perpetual securities available for sale	$60

INVESTMENTS_Investment_Exposur

INVESTMENTS - Investment Exposures Individually Exceeded Ten Percent of Shareholders' Equity (Detail) (Japan National Government, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Japan National Government
Summary of Investment Holdings [Line Items]
Credit Rating	A	AA
Amortized Cost	$37,021	$41,924
Fair Value	$41,878	$43,619

INVESTMENTS_Total_Investments_

INVESTMENTS - Total Investments in Bank and Financial Institution Sector, Including those Classified as Perpetual Securities (Detail) (Banks/financial Institutions, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Summary of Investment Holdings [Line Items]
Amortized Cost	$12,884	$15,205
Fair Value	14,121	15,375
Percentage of Total Investment Portfolio, Amortized Cost	14.00%	15.00%
Percentage of Total Investment Portfolio, Fair Value	13.00%	15.00%
Fixed maturities
Summary of Investment Holdings [Line Items]
Amortized Cost	10,627	12,427
Fair Value	11,683	12,637
Percentage of Total Investment Portfolio, Amortized Cost	11.00%	12.00%
Percentage of Total Investment Portfolio, Fair Value	11.00%	12.00%
Perpetual securities | Upper Tier II
Summary of Investment Holdings [Line Items]
Amortized Cost	1,554	1,920
Fair Value	1,645	1,913
Percentage of Total Investment Portfolio, Amortized Cost	2.00%	2.00%
Percentage of Total Investment Portfolio, Fair Value	1.00%	2.00%
Perpetual securities | Tier I
Summary of Investment Holdings [Line Items]
Amortized Cost	703	858
Fair Value	$793	$825
Percentage of Total Investment Portfolio, Amortized Cost	1.00%	1.00%
Percentage of Total Investment Portfolio, Fair Value	1.00%	1.00%

INVESTMENTS_Information_Regard

INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses realized	($31)	[1]	($199)	[1]	($977)	[1]
Derivative gains (losses)	31		326		151
Other	0		10		3
Total realized investment gains (losses)	215		399		-349
Fixed maturities
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	184		135		-349
Perpetual securities
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses realized	0		-70		-243
Total realized investment gains (losses)	0		-71		-154
Equity securities
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses realized	0		-1		0
Total realized investment gains (losses)	0		-1		0
Derivatives and other
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	31		336		154
Available-for-sale Securities | Fixed maturities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	192		316		427
Gross losses from sales	-12		-87		-48
Net gains (losses) from redemptions	34		34		2
Other-than-temporary impairment losses realized	-31		-128		-734
Available-for-sale Securities | Perpetual securities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	0		0		127
Gross losses from sales	0		-1		-98
Net gains (losses) from redemptions	0		0		60
Other-than-temporary impairment losses realized	0		-70		-243
Held-to-maturity Securities | Fixed maturities
Gain (Loss) on Investments [Line Items]
Net gains (losses) from redemptions	$1		$0		$4
[1]	Includes $45 and $597 for the years ended DecemberB 31, 2013 and 2012, respectively, for credit-related impairments; $26 and $27 for the years ended DecemberB 31, 2013 and 2012, respectively, for impairments due to severity and duration of decline in fair value; and $31, $128 and $353 for the years ended DecemberB 31, 2014, 2013 and 2012, respectively, from change in intent to sell securities

INVESTMENTS_Pretax_OtherThanTe

INVESTMENTS - Pretax Other-Than-Temporary Impairment Losses by Investment Category (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	$31	[1]	$199	[1]	$977	[1]
Credit-related impairment
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses			45		597
Severity and duration of decline in fair value impairment
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses			26		27
Change in intent impairment
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	31		128		353
Perpetual securities
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	0		70		243
Corporate Bonds
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	31		102		345
Mortgage- and asset-backed securities
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	0		0		3
Sovereign and supranational
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	0		26		386
Equity securities
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses	$0		$1		$0
[1]	Includes $45 and $597 for the years ended DecemberB 31, 2013 and 2012, respectively, for credit-related impairments; $26 and $27 for the years ended DecemberB 31, 2013 and 2012, respectively, for impairments due to severity and duration of decline in fair value; and $31, $128 and $353 for the years ended DecemberB 31, 2014, 2013 and 2012, respectively, from change in intent to sell securities

INVESTMENTS_Information_Regard1

INVESTMENTS - Information Regarding Changes in Unrealized Gains and Losses from Investments (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	$5,893	($2,418)	$2,157
Fixed maturities | Available-for-sale Securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	5,629	-2,281	1,624
Fixed maturities | Transferred to Held to Maturity Securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	-10	-9	-14
Perpetual securities | Available-for-sale Securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	269	-129	547
Equity securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	$5	$1	$0

INVESTMENTS_Net_Effect_on_Shar

INVESTMENTS - Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investments [Abstract]
Unrealized Gain (Losses) on Available-for-sale Securities	$7,426	$1,523
Unamortized unrealized gains on securities transferred to held to maturity	0	11
Deferred income taxes	-2,754	-499
Shareholders' equity, unrealized gains (losses) on investment securities	$4,672	$1,035

INVESTMENTS_Fair_Value_and_Gro

INVESTMENTS - Fair Value and Gross Unrealized Losses for Securities That Have Been in Continuous Unrealized Loss Position (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	$14,279	$36,214
Total Unrealized Losses	834	2,746
Less Than 12 months Fair Value	2,751	27,790
Less Than 12 months Unrealized Losses	83	1,376
12 months or longer Fair Value	11,528	8,424
12 months or longer Unrealized Losses	751	1,370
Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	13,496	34,828
Total Unrealized Losses	742	2,519
Less Than 12 months Fair Value	2,557	26,985
Less Than 12 months Unrealized Losses	78	1,293
12 months or longer Fair Value	10,939	7,843
12 months or longer Unrealized Losses	664	1,226
Perpetual securities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	783	1,381
Total Unrealized Losses	92	226
Less Than 12 months Fair Value	194	800
Less Than 12 months Unrealized Losses	5	82
12 months or longer Fair Value	589	581
12 months or longer Unrealized Losses	87	144
Equity securities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value		5
Total Unrealized Losses		1
Less Than 12 months Fair Value		5
Less Than 12 months Unrealized Losses		1
12 months or longer Fair Value		0
12 months or longer Unrealized Losses		0
Yen-denominated | Fixed Maturities | Japan government and agencies
Investments, Unrealized Loss Position [Line Items]
Total Fair Value		8,869
Total Unrealized Losses		34
Less Than 12 months Fair Value		8,869
Less Than 12 months Unrealized Losses		34
12 months or longer Fair Value		0
12 months or longer Unrealized Losses		0
Yen-denominated | Fixed Maturities | Public utilities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	805	2,519
Total Unrealized Losses	25	140
Less Than 12 months Fair Value	98	1,816
Less Than 12 months Unrealized Losses	1	54
12 months or longer Fair Value	707	703
12 months or longer Unrealized Losses	24	86
Yen-denominated | Fixed Maturities | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	359	1,152
Total Unrealized Losses	14	100
Less Than 12 months Fair Value	0	791
Less Than 12 months Unrealized Losses	0	34
12 months or longer Fair Value	359	361
12 months or longer Unrealized Losses	14	66
Yen-denominated | Fixed Maturities | Banks/financial Institutions
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	1,828	4,533
Total Unrealized Losses	267	570
Less Than 12 months Fair Value	166	2,322
Less Than 12 months Unrealized Losses	0	107
12 months or longer Fair Value	1,662	2,211
12 months or longer Unrealized Losses	267	463
Yen-denominated | Fixed Maturities | Other corporate
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	1,151	3,372
Total Unrealized Losses	60	272
Less Than 12 months Fair Value	122	2,296
Less Than 12 months Unrealized Losses	2	152
12 months or longer Fair Value	1,029	1,076
12 months or longer Unrealized Losses	58	120
Yen-denominated | Perpetual securities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	783	1,322
Total Unrealized Losses	92	217
Less Than 12 months Fair Value	194	748
Less Than 12 months Unrealized Losses	5	74
12 months or longer Fair Value	589	574
12 months or longer Unrealized Losses	87	143
Dollar-denominated | Fixed Maturities | Municipalities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	75	177
Total Unrealized Losses	2	12
Less Than 12 months Fair Value	53	145
Less Than 12 months Unrealized Losses	1	8
12 months or longer Fair Value	22	32
12 months or longer Unrealized Losses	1	4
Dollar-denominated | Fixed Maturities | Public utilities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	1,001	2,023
Total Unrealized Losses	36	183
Less Than 12 months Fair Value	164	1,740
Less Than 12 months Unrealized Losses	7	143
12 months or longer Fair Value	837	283
12 months or longer Unrealized Losses	29	40
Dollar-denominated | Fixed Maturities | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Total Fair Value		12
Total Unrealized Losses		1
Less Than 12 months Fair Value		12
Less Than 12 months Unrealized Losses		1
12 months or longer Fair Value		0
12 months or longer Unrealized Losses		0
Dollar-denominated | Fixed Maturities | Banks/financial Institutions
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	205	547
Total Unrealized Losses	8	33
Less Than 12 months Fair Value	53	454
Less Than 12 months Unrealized Losses	5	23
12 months or longer Fair Value	152	93
12 months or longer Unrealized Losses	3	10
Dollar-denominated | Fixed Maturities | Other corporate
Investments, Unrealized Loss Position [Line Items]
Total Fair Value	8,072	11,588
Total Unrealized Losses	330	1,170
Less Than 12 months Fair Value	1,901	8,504
Less Than 12 months Unrealized Losses	62	733
12 months or longer Fair Value	6,171	3,084
12 months or longer Unrealized Losses	268	437
Dollar-denominated | Fixed Maturities | US government and agencies
Investments, Unrealized Loss Position [Line Items]
Total Fair Value		36
Total Unrealized Losses		4
Less Than 12 months Fair Value		36
Less Than 12 months Unrealized Losses		4
12 months or longer Fair Value		0
12 months or longer Unrealized Losses		0
Dollar-denominated | Perpetual securities
Investments, Unrealized Loss Position [Line Items]
Total Fair Value		59
Total Unrealized Losses		9
Less Than 12 months Fair Value		52
Less Than 12 months Unrealized Losses		8
12 months or longer Fair Value		7
12 months or longer Unrealized Losses		$1

INVESTMENTS_Composition_of_Inv

INVESTMENTS - Composition of Investments in Unrealized Loss Position (Details)	Dec. 31, 2014	Dec. 31, 2013
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	100.00%	100.00%
Percentage of Total Unrealized Losses	100.00%	100.00%
Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	95.00%	96.00%
Percentage of Total Unrealized Losses	89.00%	92.00%
Perpetual securities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	5.00%	4.00%
Percentage of Total Unrealized Losses	11.00%	8.00%
Japan government and agencies | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	0.00%	25.00%
Percentage of Total Unrealized Losses	0.00%	1.00%
Public utilities | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	13.00%	13.00%
Percentage of Total Unrealized Losses	7.00%	12.00%
Sovereign and supranational | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	3.00%	3.00%
Percentage of Total Unrealized Losses	2.00%	4.00%
Banks/financial Institutions | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	14.00%	14.00%
Percentage of Total Unrealized Losses	33.00%	22.00%
Other corporate | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage Of Total Investments In Unrealized Loss Position	65.00%	41.00%
Percentage of Total Unrealized Losses	47.00%	53.00%
Investment Grade | Perpetual securities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	100.00%	90.00%
Investment Grade | Japan government and agencies | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	0.00%	100.00%
Investment Grade | Public utilities | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	100.00%	98.00%
Investment Grade | Sovereign and supranational | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	100.00%	100.00%
Investment Grade | Banks/financial Institutions | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	31.00%	64.00%
Investment Grade | Other corporate | Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Percentage of unrealized losses attributable to securities that were investment grade	88.00%	91.00%

INVESTMENTS_Details_of_Holding

INVESTMENTS - Details of Holdings of Perpetual Securities (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investment Holdings [Line Items]
Amortized Cost	$60,844	$59,515
Fair Value	68,270	61,038
Unrealized Gain (Loss)	7,426	1,523
Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	2,440	2,987
Fair Value	2,669	2,947
Unrealized Gain (Loss)	229	-40
Upper Tier II | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	1,554	1,920
Fair Value	1,645	1,913
Unrealized Gain (Loss)	91	-7
Upper Tier II | A | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	61	145
Fair Value	87	183
Unrealized Gain (Loss)	26	38
Upper Tier II | BBB | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	1,330	1,563
Fair Value	1,333	1,532
Unrealized Gain (Loss)	3	-31
Upper Tier II | BB or Lower | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	163	212
Fair Value	225	198
Unrealized Gain (Loss)	62	-14
Tier I | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	703	858
Fair Value	793	825
Unrealized Gain (Loss)	90	-33
Tier I | BBB | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	519	746
Fair Value	556	706
Unrealized Gain (Loss)	37	-40
Tier I | BB or Lower | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	184	112
Fair Value	237	119
Unrealized Gain (Loss)	53	7
Other subordinated - non-banks | BB or Lower | Perpetual securities
Investment Holdings [Line Items]
Amortized Cost	183	209
Fair Value	231	209
Unrealized Gain (Loss)	$48	$0

INVESTMENTS_Investments_in_Con

INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$34,242	$44,415
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Asset derivatives	802	488
Assets, fair value	73,901	64,532
Liability derivatives	2,423	837
Liabilities	101,420	106,687
Liabilities, fair value disclosure	2,423	837
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	3,020	4,109
Securities available for sale, fixed maturities, fair value	4,166	4,843
Securities available for sale, perpetual securities, amortized cost	405	463
Securities available for sale, perpetual securities, fair value	429	468
Securities held to maturity, fixed maturities, amortized cost	83	237
Securities held to maturity, fixed maturities, fair value	84	236
Asset derivatives, amortized cost	106	106
Asset derivatives	106	106
Assets, amortized cost	3,614	4,915
Assets, fair value	4,785	5,653
Liability derivatives, amortized cost	318	207
Liability derivatives	318	207
Liabilities	318	207
Liabilities, fair value disclosure	$318	$207

INVESTMENTS_Investments_in_Var

INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$34,242	$44,415
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Assets, fair value	73,901	64,532
Variable Interest Entity, Not Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	6,104	6,724
Securities available for sale, fixed maturities, fair value	6,937	6,916
Securities available for sale, perpetual securities, amortized cost	324	370
Securities available for sale, perpetual securities, fair value	330	378
Securities held to maturity, fixed maturities, amortized cost	2,564	2,949
Securities held to maturity, fixed maturities, fair value	2,829	3,039
Assets, amortized cost	8,992	10,043
Assets, fair value	$10,096	$10,333

INVESTMENTS_Securities_Lending

INVESTMENTS - Securities Lending (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Investments [Abstract]
Securities loaned total	$2,149	$5,656
Cash collateral on loaned securities	$2,193	$5,820

DERIVATIVE_INSTRUMENTS_Additio

DERIVATIVE INSTRUMENTS - Additional Information (Detail)

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Mar. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Nov. 30, 2014

Dec. 31, 2014

Jun. 30, 2013

Dec. 31, 2014

Jul. 31, 2012

Feb. 29, 2012

Dec. 31, 2014

Feb. 29, 2012

Dec. 31, 2014

Oct. 31, 2012

Sep. 30, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Mar. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

USD ($)

USD ($)

Foreign currency forwards

Cash flow hedges

Cash flow hedges

Cash flow hedges

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

3.625% senior notes due November 2024

3.625% senior notes due November 2024

3.625% senior notes due June 2023

3.625% senior notes due June 2023

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

4.00% senior notes due February 2022

4.00% senior notes due February 2022

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

July 2014 profit repatriation

December 2014 profit repatriation

December 2014 profit repatriation

Profit repatriation

Net investment hedge

Net investment hedge

Net investment hedge

Y

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Foreign currency forwards and options

Foreign currency forwards and options

Foreign currency forwards

Foreign currency forwards

USD ($)

USD ($)

USD ($)

currency

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

counterparties

Derivative Instruments and Hedging Activities Disclosure [Line Items]

Number of currencies related to foreign currency swaps

1

Number of counterparties

16

Number of counterparties that comprise majority of aggregate notional amount of swaps

5

Percentage of notional amount of swaps from certain number of counterparties

80.00%

Collateral Already Posted, Aggregate Fair Value

$1,600,000,000

$8,000,000

Derivative, Collateral, Right to Reclaim Securities

1,621,000,000

[1]

7,000,000

1,439,000,000

Derivative, Collateral, Right to Reclaim Cash

1,000,000

Derivative, Net Liability Position, Aggregate Fair Value

2,100,000,000

18,000,000

Additional Collateral, Aggregate Fair Value

482,000,000

Collateral obtained from third parties

619,000,000

295,000,000

Hedging activity, weighted-average period (in years)

11

Notes payable, principal amount

5,500,000,000

5,500,000,000

5,500,000,000

750,000,000

750,000,000

700,000,000

700,000,000

400,000,000

250,000,000

400,000,000

350,000,000

350,000,000

500,000,000

50,000,000

450,000,000

Notes payable, effective interest rate

1.48%

1.00%

1.50%

1.22%

2.07%

4.42%

4.41%

Net Derivatives Notional Amount

23,662,000,000

22,475,000,000

75,000,000

127,000,000

52,500,000,000

50,000,000,000

50,000,000,000

157,500,000,000

Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net

0

0

0

Net investment hedge gain loss reclassified to earnings net

$0

$0

$0

[1]

Consists entirely of pledged securities.

DERIVATIVE_INSTRUMENTS_Fair_Va

DERIVATIVE INSTRUMENTS - Fair Value and Notional Amounts of Derivatives With Counterparty Credit Risk (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Net Derivatives Notional Amount	$23,662	$22,475
Assets Derivatives Fair Value	802	488
Liability Derivatives Fair Value	-2,423	-837
AA
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Net Derivatives Notional Amount	1,098	161
Assets Derivatives Fair Value	39	1
Liability Derivatives Fair Value	-36	-7
A
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Net Derivatives Notional Amount	22,564	22,314
Assets Derivatives Fair Value	763	487
Liability Derivatives Fair Value	($2,387)	($830)

DERIVATIVE_INSTRUMENTS_Maximum

DERIVATIVE INSTRUMENTS - Maximum Potential Risk, Fair Value, Weighted-Average Years to Maturity, and Underlying Referenced Credit Obligation Type for Credit Default Swaps (Detail) (Corporate Bonds, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Credit Derivatives [Line Items]
Maximum potential risk	($83)	($207)
Estimated fair value	0	-3
Less than one year
Credit Derivatives [Line Items]
Maximum potential risk	0	0
Estimated fair value	0	0
One to three years
Credit Derivatives [Line Items]
Maximum potential risk	0	-112
Estimated fair value	0	1
Three to five years
Credit Derivatives [Line Items]
Maximum potential risk	-83	0
Estimated fair value	0	0
Five to ten years
Credit Derivatives [Line Items]
Maximum potential risk	0	-95
Estimated fair value	0	-4
A
Credit Derivatives [Line Items]
Credit Rating	A	A
Maximum potential risk	-83	-112
Estimated fair value	0	1
A | Less than one year
Credit Derivatives [Line Items]
Maximum potential risk	0	0
Estimated fair value	0	0
A | One to three years
Credit Derivatives [Line Items]
Maximum potential risk	0	-112
Estimated fair value	0	1
A | Three to five years
Credit Derivatives [Line Items]
Maximum potential risk	-83	0
Estimated fair value	0	0
A | Five to ten years
Credit Derivatives [Line Items]
Maximum potential risk	0	0
Estimated fair value	0	0
BBB
Credit Derivatives [Line Items]
Credit Rating		BBB
Maximum potential risk		-95
Estimated fair value		-4
BBB | Less than one year
Credit Derivatives [Line Items]
Maximum potential risk		0
Estimated fair value		0
BBB | One to three years
Credit Derivatives [Line Items]
Maximum potential risk		0
Estimated fair value		0
BBB | Three to five years
Credit Derivatives [Line Items]
Maximum potential risk		0
Estimated fair value		0
BBB | Five to ten years
Credit Derivatives [Line Items]
Maximum potential risk		-95
Estimated fair value		($4)

DERIVATIVE_INSTRUMENTS_Summary

DERIVATIVE INSTRUMENTS - Summary of Balance Sheet Classification of Derivative Fair Value Amounts, as well as Gross Asset and Liability Fair Value Amounts (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	$23,662	$22,475
Net Derivatives Fair Value	-1,621	-349
Asset Derivatives Fair Value	802	488
Liability Derivatives Fair Value	-2,423	-837
Other assets
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	6,531	5,308
Net Derivatives Fair Value	802	488
Asset Derivatives Fair Value	802	488
Liability Derivatives Fair Value	0	0
Other Liabilities
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	17,131	17,167
Net Derivatives Fair Value	-2,423	-837
Asset Derivatives Fair Value	0	0
Liability Derivatives Fair Value	-2,423	-837
Foreign currency swaps
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	746	445
Liability Derivatives Fair Value	-318	-218
Foreign currency forwards
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	56	17
Liability Derivatives Fair Value	-1,912	-582
Foreign currency options
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value		4
Liability Derivatives Fair Value	-33	-1
Interest rate swaptions
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value		20
Liability Derivatives Fair Value	-160	-32
Interest rate swaps
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value		1
Credit default swaps
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value		1
Liability Derivatives Fair Value		-4
Cash flow hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	127
Net Derivatives Fair Value	-15	3
Asset Derivatives Fair Value	0	3
Liability Derivatives Fair Value	-15	0
Cash flow hedges | Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	75
Net Derivatives Fair Value	-15	3
Asset Derivatives Fair Value	0	3
Liability Derivatives Fair Value	-15	0
Cash flow hedges | Interest rate swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount		52
Net Derivatives Fair Value		0
Asset Derivatives Fair Value		0
Liability Derivatives Fair Value		0
Fair value hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	15,587	15,749
Net Derivatives Fair Value	-1,982	-594
Asset Derivatives Fair Value	0	20
Liability Derivatives Fair Value	-1,982	-614
Fair value hedges | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	12,388	11,249
Net Derivatives Fair Value	-1,791	-582
Asset Derivatives Fair Value	0	0
Liability Derivatives Fair Value	-1,791	-582
Fair value hedges | Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	697
Net Derivatives Fair Value	-32
Asset Derivatives Fair Value	0
Liability Derivatives Fair Value	-32
Fair value hedges | Interest rate swaptions
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	2,502	4,500
Net Derivatives Fair Value	-159	-12
Asset Derivatives Fair Value	0	20
Liability Derivatives Fair Value	-159	-32
Net investment hedge
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	1,307	451
Net Derivatives Fair Value	54	20
Asset Derivatives Fair Value	56	21
Liability Derivatives Fair Value	-2	-1
Net investment hedge | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	1,307	356
Net Derivatives Fair Value	54	17
Asset Derivatives Fair Value	56	17
Liability Derivatives Fair Value	-2	0
Net investment hedge | Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount		95
Net Derivatives Fair Value		3
Asset Derivatives Fair Value		4
Liability Derivatives Fair Value		-1
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	6,693	6,148
Net Derivatives Fair Value	322	222
Asset Derivatives Fair Value	746	444
Liability Derivatives Fair Value	-424	-222
Non-qualifying strategies | Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	5,765	5,829
Net Derivatives Fair Value	443	224
Asset Derivatives Fair Value	746	442
Liability Derivatives Fair Value	-303	-218
Non-qualifying strategies | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	784
Net Derivatives Fair Value	-119
Asset Derivatives Fair Value	0
Liability Derivatives Fair Value	-119
Non-qualifying strategies | Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	53
Net Derivatives Fair Value	-1
Asset Derivatives Fair Value	0
Liability Derivatives Fair Value	-1
Non-qualifying strategies | Interest rate swaptions
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	8
Net Derivatives Fair Value	-1
Asset Derivatives Fair Value	0
Liability Derivatives Fair Value	-1
Non-qualifying strategies | Interest rate swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount		112
Net Derivatives Fair Value		1
Asset Derivatives Fair Value		1
Liability Derivatives Fair Value		0
Non-qualifying strategies | Credit default swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	83	207
Net Derivatives Fair Value	0	-3
Asset Derivatives Fair Value	0	1
Liability Derivatives Fair Value	$0	($4)

DERIVATIVE_INSTRUMENTS_Gains_L

DERIVATIVE INSTRUMENTS - Gains (Losses) Recognized on Fair Value Hedging Relationships (Details) (Fixed Maturities, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	($1,835)	($1,735)	($535)
Gains (losses) on derivatives excluded from effectiveness testing	-38	-25	-8
Gains (losses) on derivatives included in effectiveness testing	-1,797	-1,710	-527
Gains (losses) recognized for hedged items	1,819	1,700	528
Ineffectiveness recognized for fair value hedge	22	-10	1
Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	-41
Gains (losses) on derivatives excluded from effectiveness testing	-4
Gains (losses) on derivatives included in effectiveness testing	-37
Gains (losses) recognized for hedged items	38
Ineffectiveness recognized for fair value hedge	1
Interest rate swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	-318	17
Gains (losses) on derivatives excluded from effectiveness testing	-36	17
Gains (losses) on derivatives included in effectiveness testing	-282	0
Gains (losses) recognized for hedged items	316	0
Ineffectiveness recognized for fair value hedge	$34	$0

DERIVATIVE_INSTRUMENTS_Derivat

DERIVATIVE INSTRUMENTS - Derivatives and Hedging Instruments Gain (Loss) Summary (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized foreign currency translation gains (losses) during period	($1,455)		($1,588)		($287)
Derivative and other gains (losses)	31		326		151
Derivative and non-derivative hedging instruments gain loss recognized in other comprehensive income effective portion before tax	108	[1]	69	[1]	74	[1]
Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-2		-2		-3
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	-17	[1]	-10	[1]	-22	[1]
Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-21		-18		-7
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0		0
Unrealized foreign currency translation gains (losses) during period	125	[1]	79	[1]	96	[1]
Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	54		346		161
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Foreign currency swaps | Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-2		-2		-3
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	-17	[1]	-10	[1]	-22	[1]
Foreign currency swaps | Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0		0
Unrealized foreign currency translation gains (losses) during period	0	[1]	-104	[1]	0	[1]
Foreign currency swaps | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	151		346		111
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Interest rate swaps | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	-1		-8		-14
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Foreign currency forwards | Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-16	[2]	-35	[2]	-7	[2]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1],[2]	0	[1],[2]	0	[1],[2]
Foreign currency forwards | Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0		0
Unrealized foreign currency translation gains (losses) during period	89	[1]	24	[1]	0	[1]
Foreign currency forwards | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	-11		0		0
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Interest rate swaptions | Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-2	[2]	17	[2]	0	[2]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1],[2]	0	[1],[2]	0	[1],[2]
Interest rate swaptions | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	1		-29		0
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Non-derivative hedging instruments | Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0		0
Unrealized foreign currency translation gains (losses) during period	39	[1]	155	[1]	96	[1]
Foreign currency options | Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	-3	[2]	0	[2]	0	[2]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1],[2]	0	[1],[2]	0	[1],[2]
Foreign currency options | Net investment hedge
Derivative Instruments, Gain (Loss) [Line Items]
Net Realized Investment Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0		0
Unrealized foreign currency translation gains (losses) during period	-3	[1]	4	[1]	0	[1]
Foreign currency options | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	0		11		0
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Credit default swaps | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	3		31		64
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	[1]	0	[1]	0	[1]
Futures | Non-qualifying strategies
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instrument, Gain (Loss) Recognized in Income, Net	-89		-5		0
Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	$0	[1]	$0	[1]	$0	[1]
[1]	Cash flow hedge items 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 shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail)

DERIVATIVE_INSTRUMENTS_Offsett

DERIVATIVE INSTRUMENTS - Offsetting of Financial Assets and Derivative Assets (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	$802		$488
Gross amount of liabilities offset in balance sheet	0		0
Net amount of derivative assets presented in balance sheet	802		488
Financial instruments, amount not offset against derivative assets in balance sheet	0		0
Derivative, Collateral, Obligation to Return Cash and Securities	-619	[1]
Derivative, Collateral, Obligation to Return Cash	-466		-295	[2]
Derivative asset, fair value, amount offset against collateral	183		193
Derivative, Collateral, Obligation to Return Securities	-153
Foreign currency swaps
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	746		445
Gross amount of liabilities offset in balance sheet	0		0
Net amount of derivative assets presented in balance sheet	746		445
Financial instruments, amount not offset against derivative assets in balance sheet	0		0
Derivative, Collateral, Obligation to Return Cash and Securities	-568
Derivative, Collateral, Obligation to Return Cash			-276
Derivative asset, fair value, amount offset against collateral	178		169
Foreign currency forwards
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	56		17
Gross amount of liabilities offset in balance sheet	0		0
Net amount of derivative assets presented in balance sheet	56		17
Financial instruments, amount not offset against derivative assets in balance sheet	0		0
Derivative, Collateral, Obligation to Return Cash and Securities	-51
Derivative, Collateral, Obligation to Return Cash			-16
Derivative asset, fair value, amount offset against collateral	5		1
Foreign currency options
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets			4
Gross amount of liabilities offset in balance sheet			0
Net amount of derivative assets presented in balance sheet			4
Financial instruments, amount not offset against derivative assets in balance sheet			0
Derivative, Collateral, Obligation to Return Cash			-3
Derivative asset, fair value, amount offset against collateral			1
Credit default swaps
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets			1
Gross amount of liabilities offset in balance sheet			0
Net amount of derivative assets presented in balance sheet			1
Financial instruments, amount not offset against derivative assets in balance sheet			0
Derivative, Collateral, Obligation to Return Cash			0
Derivative asset, fair value, amount offset against collateral			1
Interest rate swaps
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets			1
Gross amount of liabilities offset in balance sheet			0
Net amount of derivative assets presented in balance sheet			1
Financial instruments, amount not offset against derivative assets in balance sheet			0
Derivative, Collateral, Obligation to Return Cash			0
Derivative asset, fair value, amount offset against collateral			1
Interest rate swaptions
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets			20
Gross amount of liabilities offset in balance sheet			0
Net amount of derivative assets presented in balance sheet			20
Financial instruments, amount not offset against derivative assets in balance sheet			0
Derivative, Collateral, Obligation to Return Cash			0
Derivative asset, fair value, amount offset against collateral			20
Offsetting assets
Offsetting Assets [Line Items]
Gross amounts of recognized financial instruments	2,951		6,144
Gross amounts offset in balance sheet	0		0
Net amounts of financial instruments presented in balance sheet	2,951		6,144
Carrying value of financial instruments not offset in balance sheet	0		0
Collateral not offset in balance sheet	-2,768		-5,951
Financial instruments, amount offset against collateral	183		193
Offsetting assets | Securities lending and similar arrangements
Offsetting Assets [Line Items]
Gross amounts of recognized financial instruments	2,149		5,656
Gross amounts offset in balance sheet	0		0
Net amounts of financial instruments presented in balance sheet	2,149		5,656
Carrying value of financial instruments not offset in balance sheet	0		0
Collateral not offset in balance sheet	-2,149		-5,656
Financial instruments, amount offset against collateral	$0		$0
[1]	Consists of $153 of pledged securities and $466 of cash.
[2]	Consists entirely of cash.

DERIVATIVE_INSTRUMENTS_Offsett1

DERIVATIVE INSTRUMENTS - Offsetting of Financial Liabilities and Derivative Liabilities (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	($2,423)		($837)
Gross amount of assets offset in balance sheet	0		0
Net amount of derivative liabilities presented in balance sheet	-2,423		-837
Financial instruments, amount not offset against derivative liabilities in balance sheet	0		0
Derivative, Collateral, Right to Reclaim Securities	1,621	[1]	7
Derivative, Collateral, Right to Reclaim Cash			1
Derivative, Collateral, Right to Reclaim Securities and Cash			8	[2]
Derivative Liability, Fair Value, Amount Offset Against Collateral	-802		-829
Foreign currency swaps
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	-318		-218
Gross amount of assets offset in balance sheet	0		0
Net amount of derivative liabilities presented in balance sheet	-318		-218
Financial instruments, amount not offset against derivative liabilities in balance sheet	0		0
Derivative, Collateral, Right to Reclaim Securities	0
Derivative, Collateral, Right to Reclaim Securities and Cash			1
Derivative Liability, Fair Value, Amount Offset Against Collateral	-318		-217
Foreign currency forwards
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	-1,912		-582
Gross amount of assets offset in balance sheet	0		0
Net amount of derivative liabilities presented in balance sheet	-1,912		-582
Financial instruments, amount not offset against derivative liabilities in balance sheet	0		0
Derivative, Collateral, Right to Reclaim Securities	1,439
Derivative, Collateral, Right to Reclaim Securities and Cash			0
Derivative Liability, Fair Value, Amount Offset Against Collateral	-473		-582
Foreign currency options
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	-33		-1
Gross amount of assets offset in balance sheet	0		0
Net amount of derivative liabilities presented in balance sheet	-33		-1
Financial instruments, amount not offset against derivative liabilities in balance sheet	0		0
Derivative, Collateral, Right to Reclaim Securities	24
Derivative, Collateral, Right to Reclaim Securities and Cash			0
Derivative Liability, Fair Value, Amount Offset Against Collateral	-9		-1
Credit default swaps
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities			-4
Gross amount of assets offset in balance sheet			0
Net amount of derivative liabilities presented in balance sheet			-4
Financial instruments, amount not offset against derivative liabilities in balance sheet			0
Derivative, Collateral, Right to Reclaim Securities and Cash			0
Derivative Liability, Fair Value, Amount Offset Against Collateral			-4
Interest rate swaptions
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	-160		-32
Gross amount of assets offset in balance sheet	0		0
Net amount of derivative liabilities presented in balance sheet	-160		-32
Financial instruments, amount not offset against derivative liabilities in balance sheet	0		0
Derivative, Collateral, Right to Reclaim Securities	158
Derivative, Collateral, Right to Reclaim Securities and Cash			7
Derivative Liability, Fair Value, Amount Offset Against Collateral	-2		-25
Offsetting liabilities
Offsetting Liabilities [Line Items]
Gross amounts of recognized financial instruments	-4,616		-6,657
Gross amounts offset in balance sheet	0		0
Net amounts of financial instruments presented in balance sheet	-4,616		-6,657
Carrying value of financial instruments not offset in balance sheet	2,149		5,656
Collateral not offset in balance sheet	1,621		8
Financial instruments, amount offset against collateral	-846		-993
Offsetting liabilities | Securities lending and similar arrangements
Offsetting Liabilities [Line Items]
Gross amounts of recognized financial instruments	-2,193		-5,820
Gross amounts offset in balance sheet	0		0
Net amounts of financial instruments presented in balance sheet	-2,193		-5,820
Carrying value of financial instruments not offset in balance sheet	2,149		5,656
Collateral not offset in balance sheet	0		0
Financial instruments, amount offset against collateral	($44)		($164)
[1]	Consists entirely of pledged securities.
[2]	Consists of $7 of pledged securities and $1 of cash.

FAIR_VALUE_MEASUREMENTS_Fair_V

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Assets:
Available-for-sale Securities	$68,270	$61,038
Asset derivatives	802	488
Other Investments	171	463
Cash and cash equivalents	4,658	2,543
Assets, fair value	73,901	64,532
Liabilities:
Liability derivatives	2,423	837
Total Liabilities	2,423	837
Foreign currency swaps
Assets:
Asset derivatives	746	445
Liabilities:
Liability derivatives	318	218
Foreign currency forwards
Assets:
Asset derivatives	56	17
Liabilities:
Liability derivatives	1,912	582
Foreign currency options
Assets:
Asset derivatives		4
Liabilities:
Liability derivatives	33	1
Credit default swaps
Assets:
Asset derivatives		1
Liabilities:
Liability derivatives		4
Interest rate swaps
Assets:
Asset derivatives		1
Interest rate swaptions
Assets:
Asset derivatives		20
Liabilities:
Liability derivatives	160	32
Fixed Maturities
Assets:
Available-for-sale Securities	65,573	58,070
Fixed Maturities | Government and agencies
Assets:
Available-for-sale Securities	19,198	15,432
Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,257	1,051
Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	602	771
Fixed Maturities | Public utilities
Assets:
Available-for-sale Securities	7,897	7,562
Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	1,416	1,523
Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,598	6,509
Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	28,605	25,222
Perpetual securities
Assets:
Available-for-sale Securities	2,669	2,947
Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,438	2,738
Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	231	209
Equity securities
Assets:
Available-for-sale Securities	28	21
Level 1
Assets:
Available-for-sale Securities	18,702	14,942
Asset derivatives	0	0
Other Investments	171	463
Cash and cash equivalents	4,658	2,543
Assets, fair value	23,531	17,948
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 | Credit default swaps
Assets:
Asset derivatives		0
Liabilities:
Liability derivatives		0
Level 1 | Interest rate swaps
Assets:
Asset derivatives		0
Level 1 | Interest rate swaptions
Assets:
Asset derivatives		0
Liabilities:
Liability derivatives	0	0
Level 1 | Fixed Maturities
Assets:
Available-for-sale Securities	18,683	14,928
Level 1 | Fixed Maturities | Government and agencies
Assets:
Available-for-sale Securities	18,683	14,928
Level 1 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Public utilities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Equity securities
Assets:
Available-for-sale Securities	19	14
Level 2
Assets:
Available-for-sale Securities	49,167	45,649
Asset derivatives	696	382
Other Investments	0	0
Cash and cash equivalents	0	0
Assets, fair value	49,863	46,031
Liabilities:
Total Liabilities	2,105	630
Level 2 | Foreign currency swaps
Assets:
Asset derivatives	640	341
Liabilities:
Liability derivatives	0	15
Level 2 | Foreign currency forwards
Assets:
Asset derivatives	56	17
Liabilities:
Liability derivatives	1,912	582
Level 2 | Foreign currency options
Assets:
Asset derivatives		4
Liabilities:
Liability derivatives	33	1
Level 2 | Credit default swaps
Assets:
Asset derivatives		0
Liabilities:
Liability derivatives		0
Level 2 | Interest rate swaps
Assets:
Asset derivatives		0
Level 2 | Interest rate swaptions
Assets:
Asset derivatives		20
Liabilities:
Liability derivatives	160	32
Level 2 | Fixed Maturities
Assets:
Available-for-sale Securities	46,641	42,750
Level 2 | Fixed Maturities | Government and agencies
Assets:
Available-for-sale Securities	515	504
Level 2 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,257	1,051
Level 2 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	379	402
Level 2 | Fixed Maturities | Public utilities
Assets:
Available-for-sale Securities	7,897	7,562
Level 2 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	1,416	1,523
Level 2 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,572	6,486
Level 2 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	28,605	25,222
Level 2 | Perpetual securities
Assets:
Available-for-sale Securities	2,520	2,895
Level 2 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,289	2,686
Level 2 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	231	209
Level 2 | Equity securities
Assets:
Available-for-sale Securities	6	4
Level 3
Assets:
Available-for-sale Securities	401	447
Asset derivatives	106	106
Other Investments	0	0
Cash and cash equivalents	0	0
Assets, fair value	507	553
Liabilities:
Total Liabilities	318	207
Level 3 | Foreign currency swaps
Assets:
Asset derivatives	106	104
Liabilities:
Liability derivatives	318	203
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 | Credit default swaps
Assets:
Asset derivatives		1
Liabilities:
Liability derivatives		4
Level 3 | Interest rate swaps
Assets:
Asset derivatives		1
Level 3 | Interest rate swaptions
Assets:
Asset derivatives		0
Liabilities:
Liability derivatives	0	0
Level 3 | Fixed Maturities
Assets:
Available-for-sale Securities	249	392
Level 3 | Fixed Maturities | Government and agencies
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	223	369
Level 3 | Fixed Maturities | Public utilities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	26	23
Level 3 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Perpetual securities
Assets:
Available-for-sale Securities	149	52
Level 3 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	149	52
Level 3 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Equity securities
Assets:
Available-for-sale Securities	3	3
Consensus pricing valuation technique | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	223	369
Consensus pricing valuation technique | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	84	23
Consensus pricing valuation technique | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities		2
Consensus pricing valuation technique | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	149
Consensus pricing valuation technique | Level 1 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	0	0
Consensus pricing valuation technique | Level 1 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Consensus pricing valuation technique | Level 1 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities		0
Consensus pricing valuation technique | Level 1 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0
Consensus pricing valuation technique | Level 2 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	0	0
Consensus pricing valuation technique | Level 2 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	58	0
Consensus pricing valuation technique | Level 2 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities		2
Consensus pricing valuation technique | Level 2 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0
Consensus pricing valuation technique | Level 3 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	223	369
Consensus pricing valuation technique | Level 3 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	26	23
Consensus pricing valuation technique | Level 3 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities		0
Consensus pricing valuation technique | Level 3 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	$149	$52

FAIR_VALUE_MEASUREMENTS_Fair_V1

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Assets:
Securities held to maturity, fixed maturities, amortized cost	$34,242	$44,415
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Liabilities:
Other Policyholder Funds	6,031	5,861
Other policyholders' funds fair value disclosure	5,905	5,715
Notes Payable	5,268	4,891
Notes Payable, Fair Value Disclosure	5,835	5,241
Total Financial Instrument Liabilities Not Carried At Fair Value	11,299	10,752
Liabilities Fair Value Disclosure Financial Instruments Carried At Cost	11,740	10,956
Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	34,242	44,415
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Japan government and agencies | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	20,023	27,362
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Municipalities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	346	399
Securities held to maturity, fixed maturities, fair value	417	440
Mortgage- and asset-backed securities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	43	58
Securities held to maturity, fixed maturities, fair value	46	61
Public utilities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	3,342	3,900
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Sovereign and supranational | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	2,556	2,941
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Banks/financial Institutions | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	4,932	6,310
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Other corporate | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, amortized cost	3,000	3,445
Securities held to maturity, fixed maturities, fair value	3,314	3,541
Level 1
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 | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Level 1 | Japan government and agencies | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Level 1 | Municipalities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 1 | Mortgage- and asset-backed securities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 1 | Public utilities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 1 | Sovereign and supranational | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 1 | Banks/financial Institutions | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 1 | Other corporate | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 2
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 2 | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	15,248	17,097
Level 2 | Japan government and agencies | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 2 | Municipalities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	417	440
Level 2 | Mortgage- and asset-backed securities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	15	20
Level 2 | Public utilities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Level 2 | Sovereign and supranational | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Level 2 | Banks/financial Institutions | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Level 2 | Other corporate | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	3,314	3,541
Level 3
Liabilities:
Other policyholders' funds fair value disclosure	5,905	5,715
Notes Payable, Fair Value Disclosure	5,835	5,241
Liabilities Fair Value Disclosure Financial Instruments Carried At Cost	11,740	10,956
Level 3 | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	31	41
Level 3 | Japan government and agencies | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 3 | Municipalities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 3 | Mortgage- and asset-backed securities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	31	41
Level 3 | Public utilities | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 3 | Sovereign and supranational | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 3 | Banks/financial Institutions | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	0	0
Level 3 | Other corporate | Fixed Maturities
Assets:
Securities held to maturity, fixed maturities, fair value	$0	$0

FAIR_VALUE_MEASUREMENTS_Fair_V2

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets by Pricing Source, Available-for-sale Securities (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	$68,270	$61,038
Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	18,702	14,942
Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	49,167	45,649
Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	401	447
Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	65,573	58,070
Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	18,683	14,928
Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	46,641	42,750
Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	249	392
Perpetual securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,669	2,947
Perpetual securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Perpetual securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,520	2,895
Perpetual securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	149	52
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	28	21
Equity securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	19	14
Equity securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6	4
Equity securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	3	3
Equity securities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	25	18
Equity securities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	19	14
Equity securities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6	4
Equity securities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Equity securities | Net asset value valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	3	3
Equity securities | Net asset value valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Equity securities | Net asset value valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Equity securities | Net asset value valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	3	3
Government and agencies | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	19,198	15,432
Government and agencies | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	18,683	14,928
Government and agencies | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	515	504
Government and agencies | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	19,198	15,432
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	18,683	14,928
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	515	504
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Municipalities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,257	1,051
Municipalities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Municipalities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,257	1,051
Municipalities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,257	1,051
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,257	1,051
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	602	771
Mortgage- and asset-backed securities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	379	402
Mortgage- and asset-backed securities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	223	369
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	379	402
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	379	402
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	223	369
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	223	369
Public utilities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	7,897	7,562
Public utilities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Public utilities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	7,897	7,562
Public utilities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	7,897	7,562
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	7,897	7,562
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Sovereign and supranational | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,416	1,523
Sovereign and supranational | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Sovereign and supranational | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,416	1,523
Sovereign and supranational | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,416	1,523
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	1,416	1,523
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6,598	6,509
Banks/financial Institutions | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6,572	6,486
Banks/financial Institutions | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	26	23
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6,514	6,486
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	6,514	6,486
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	84	23
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	58	0
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	26	23
Banks/financial Institutions | Perpetual securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,438	2,738
Banks/financial Institutions | Perpetual securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Perpetual securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,289	2,686
Banks/financial Institutions | Perpetual securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	149	52
Banks/financial Institutions | Perpetual securities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,289	2,738
Banks/financial Institutions | Perpetual securities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Banks/financial Institutions | Perpetual securities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	2,289	2,686
Banks/financial Institutions | Perpetual securities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	52
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	149
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	149	52
Other corporate | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	28,605	25,222
Other corporate | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	28,605	25,222
Other corporate | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	28,605	25,220
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	28,605	25,220
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Fixed Maturities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities		2
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities		0
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities		2
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities		0
Other corporate | Perpetual securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	231	209
Other corporate | Perpetual securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Perpetual securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	231	209
Other corporate | Perpetual securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Perpetual securities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	231	209
Other corporate | Perpetual securities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	0	0
Other corporate | Perpetual securities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	231	209
Other corporate | Perpetual securities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale Securities	$0	$0

FAIR_VALUE_MEASUREMENTS_Fair_V3

FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels by Pricing Source, Held-to-Maturity Securities (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	$38,497	$45,846
Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	15,248	17,097
Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	31	41
Government and agencies | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Government and agencies | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Government and agencies | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Government and agencies | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	23,218	28,708
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Government and agencies | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Municipalities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	417	440
Municipalities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Municipalities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	417	440
Municipalities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	417	440
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	417	440
Municipalities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	46	61
Mortgage- and asset-backed securities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	15	20
Mortgage- and asset-backed securities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	31	41
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	15	20
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	15	20
Mortgage- and asset-backed securities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	31	41
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	31	41
Public utilities | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Public utilities | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Public utilities | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Public utilities | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,603	3,928
Public utilities | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Sovereign and supranational | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Sovereign and supranational | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Sovereign and supranational | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Sovereign and supranational | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	2,814	3,040
Sovereign and supranational | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Banks/financial Institutions | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Banks/financial Institutions | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Banks/financial Institutions | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Banks/financial Institutions | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	5,085	6,128
Banks/financial Institutions | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,314	3,541
Other corporate | Fixed Maturities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,314	3,541
Other corporate | Fixed Maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,287	3,509
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	3,287	3,509
Other corporate | Fixed Maturities | Third party pricing vendor valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities | Consensus pricing valuation technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	27	32
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	0	0
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	27	32
Other corporate | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity, fixed maturities, fair value	$0	$0

FAIR_VALUE_MEASUREMENTS_Change

FAIR VALUE MEASUREMENTS - Changes in Available-For-Sale Investments and Derivatives Classified as Level 3 (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$346		$3,197
Realized gains or losses included in earnings	-189		105
Unrealized gains or losses included in other comprehensive income	-140		-105
Purchases	0		0
Issuances	0		0
Sales	-60		-387
Settlements	83		-13
Transfers into Level 3	149	[1]	174	[2]
Transfers out of Level 3	0		-2,625	[3]
Balance, end of period	189		346
Change in unrealized gain (losses) still held	-189		105
Fixed Maturities | Mortgage- and asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	369		338
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	-134		-72
Purchases	0		0
Issuances	0		0
Sales	0		0
Settlements	-12		-13
Transfers into Level 3	0	[1]	125	[2]
Transfers out of Level 3	0		-9	[3]
Balance, end of period	223		369
Change in unrealized gain (losses) still held	0		0
Fixed Maturities | Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0		420
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	0		-20
Purchases	0		0
Issuances	0		0
Sales	0		-400
Settlements	0		0
Transfers into Level 3	0	[1]	0	[2]
Transfers out of Level 3	0		0	[3]
Balance, end of period	0		0
Change in unrealized gain (losses) still held	0		0
Fixed Maturities | Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0		418
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	0		0
Purchases	0		0
Issuances	0		0
Sales	0		0
Settlements	0		0
Transfers into Level 3	0	[1]	0	[2]
Transfers out of Level 3	0		-418	[3]
Balance, end of period	0		0
Change in unrealized gain (losses) still held	0		0
Fixed Maturities | Banks/financial Institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	23		1,024
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	3		-4
Purchases	0		0
Issuances	0		0
Sales	0		0
Settlements	0		0
Transfers into Level 3	0	[1]	0	[2]
Transfers out of Level 3	0		-997	[3]
Balance, end of period	26		23
Change in unrealized gain (losses) still held	0		0
Fixed Maturities | Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0		986
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	0		0
Purchases	0		0
Issuances	0		0
Sales	0		0
Settlements	0		0
Transfers into Level 3	0	[1]	0	[2]
Transfers out of Level 3	0		-986	[3]
Balance, end of period	0		0
Change in unrealized gain (losses) still held	0		0
Perpetual securities | Banks/financial Institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	52		215
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	8		3
Purchases	0		0
Issuances	0		0
Sales	-60		0
Settlements	0		0
Transfers into Level 3	149	[1]	49	[2]
Transfers out of Level 3	0		-215	[3]
Balance, end of period	149		52
Change in unrealized gain (losses) still held	0		0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	3		4
Realized gains or losses included in earnings	0		0
Unrealized gains or losses included in other comprehensive income	0		-1
Purchases	0		0
Issuances	0		0
Sales	0		0
Settlements	0		0
Transfers into Level 3	0	[1]	0	[2]
Transfers out of Level 3	0		0	[3]
Balance, end of period	3		3
Change in unrealized gain (losses) still held	0		0
Derivatives | Interest rate swaps
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	1	[4]	29	[4]
Realized gains or losses included in earnings	-1	[4]	-8	[4]
Unrealized gains or losses included in other comprehensive income	0	[4]	0	[4]
Purchases	0	[4]	0	[4]
Issuances	0	[4]	0	[4]
Sales	0	[4]	-20	[4]
Settlements	0	[4]	0	[4]
Transfers into Level 3	0	[1],[4]	0	[2],[4]
Transfers out of Level 3	0	[4]	0	[3],[4]
Balance, end of period	0	[4]	1	[4]
Change in unrealized gain (losses) still held	-1	[4]	-8	[4]
Derivatives | Foreign currency swaps
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	-99	[4]	-172	[4]
Realized gains or losses included in earnings	-191	[4]	84	[4]
Unrealized gains or losses included in other comprehensive income	-17	[4]	-11	[4]
Purchases	0	[4]	0	[4]
Issuances	0	[4]	0	[4]
Sales	0	[4]	0	[4]
Settlements	95	[4]	0	[4]
Transfers into Level 3	0	[1],[4]	0	[2],[4]
Transfers out of Level 3	0	[4]	0	[3],[4]
Balance, end of period	-212	[4]	-99	[4]
Change in unrealized gain (losses) still held	-191	[4]	84	[4]
Derivatives | Credit default swaps
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	-3	[4]	-65	[4]
Realized gains or losses included in earnings	3	[4]	29	[4]
Unrealized gains or losses included in other comprehensive income	0	[4]	0	[4]
Purchases	0	[4]	0	[4]
Issuances	0	[4]	0	[4]
Sales	0	[4]	33	[4]
Settlements	0	[4]	0	[4]
Transfers into Level 3	0	[1],[4]	0	[2],[4]
Transfers out of Level 3	0	[4]	0	[3],[4]
Balance, end of period	0	[4]	-3	[4]
Change in unrealized gain (losses) still held	$3	[4]	$29	[4]
[1]	Due to use of estimated redemption price
[2]	Due to a lack of visibility to observe significant inputs to price
[3]	A result of changing our pricing methodology to a valuation method that uses observable market data as significant inputs to estimate fair value
[4]	Derivative assets and liabilities are presented net

FAIR_VALUE_MEASUREMENTS_Additi

FAIR VALUE MEASUREMENTS - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value Disclosures [Abstract]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$0	$0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$0	$0

FAIR_VALUE_MEASUREMENTS_Fair_V4

FAIR VALUE MEASUREMENTS - Fair Value Inputs Assets Quantitative Information (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	$68,270		$61,038
Asset derivatives	802		488
Assets, fair value	73,901		64,532
Length of Volatility of Japanese Yen to US Dollar Exchange Rate	10 years		10 years
Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	401		447
Asset derivatives	106		106
Assets, fair value	507		553
Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	65,573		58,070
Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	249		392
Perpetual securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	2,669		2,947
Perpetual securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	149		52
Equity securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	28		21
Equity securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity securities | Net asset value valuation technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity securities | Net asset value valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity securities | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$1		$1
Equity securities | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$677		$774
Equity securities | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$6		$7
Mortgage- and asset-backed securities | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	602		771
Mortgage- and asset-backed securities | Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	223		369
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	223		369
Mortgage- and asset-backed securities | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	223		369
Banks/financial Institutions | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	6,598		6,509
Banks/financial Institutions | Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	26		23
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	84		23
Banks/financial Institutions | Fixed Maturities | Consensus pricing valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	26		23
Banks/financial Institutions | Perpetual securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	2,438		2,738
Banks/financial Institutions | Perpetual securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	149		52
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	149
Banks/financial Institutions | Perpetual securities | Consensus pricing valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	149		52
Foreign currency swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	746		445
Foreign currency swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	106		104
Credit default swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Credit default swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Credit default swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			0.65%
Fair Value Inputs, Base Correlation			65.00%	[1]
Credit default swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			1.06%
Fair Value Inputs, Base Correlation			76.00%	[1]
Credit default swaps | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			0.92%
Fair Value Inputs, Base Correlation			72.00%	[1]
Fair Value Inputs, Recovery Rate			37.00%
Interest rate swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Interest rate swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Interest rate swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			0.65%
Fair Value Inputs, Base Correlation			65.00%	[1]
Interest rate swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			1.06%
Fair Value Inputs, Base Correlation			76.00%	[1]
Interest rate swaps | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			0.92%
Fair Value Inputs, Base Correlation			72.00%	[1]
Fair Value Inputs, Recovery Rate			37.00%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	8		30
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.16%		0.16%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.05%		1.41%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			9
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			0.17%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk			1.49%
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	98		65
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair value, unobservable input, base correlation, CDS spreads, recovery rate | Credit default swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Fair value, unobservable input, base correlation, CDS spreads, recovery rate | Interest rate swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Yen-denominated | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	29,288		25,998
Yen-denominated | Mortgage- and asset-backed securities | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	386		587
Yen-denominated | Banks/financial Institutions | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	2,888		2,777
Yen-denominated | Banks/financial Institutions | Perpetual securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	2,263		2,516
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate			0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate			2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Dollar-denominated | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	36,285		32,072
Dollar-denominated | Mortgage- and asset-backed securities | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	216		184
Dollar-denominated | Banks/financial Institutions | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3,710		3,732
Dollar-denominated | Banks/financial Institutions | Perpetual securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	$175		$222
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate			3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate			3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
[1]	Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
[2]	Based on 10 year volatility of JPY/USD exchange rate
[3]	Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
[4]	Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps

FAIR_VALUE_MEASUREMENTS_Fair_V5

FAIR VALUE MEASUREMENTS - Fair Value Inputs Liabilities Quantitative Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	$2,423		$837
Liabilities, fair value disclosure	2,423		837
Length of Volatility of Japanese Yen to US Dollar Exchange Rate	10 years		10 years
Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities, fair value disclosure	318		207
Foreign currency swaps
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	318		218
Foreign currency swaps | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	318		203
Credit default swaps
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			4
Credit default swaps | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			4
Credit default swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			65.00%	[1]
Fair Value Inputs, Entity Credit Risk			0.65%
Credit default swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			76.00%	[1]
Fair Value Inputs, Entity Credit Risk			1.06%
Credit default swaps | Liability | Weighted Average | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			72.00%	[1]
Fair Value Inputs, Entity Credit Risk			0.92%
Fair Value Inputs, Recovery Rate			37.00%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	176		99
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.16%		0.16%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.05%		1.41%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	111		24
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.13%		0.11%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.45%		1.89%
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	31		80
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair value, unobservable input, base correlation, CDS spreads, recovery rate | Credit default swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			$4
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
[1]	Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices
[2]	Based on 10 year volatility of JPY/USD exchange rate
[3]	Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps
[4]	Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps

DEFERRED_POLICY_ACQUISITION_CO2

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Additional Information (Detail) (USD $)	12 Months Ended
In Billions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred Policy Acquisition Costs and Insurance Expense Disclosure [Abstract]
Consolidated policy acquisition costs deferred	$1.30	$1.40	$1.70
Commissions deferred as a percentage of total acquisition costs	77.00%	81.00%	84.00%
Personnel, compensation and benefit expenses as a percentage of insurance expenses	52.00%	51.00%	51.00%

DEFERRED_POLICY_ACQUISITION_CO3

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Rollforward of Deferred Policy Acquisition Costs by Segment (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred policy acquisition costs:
Balance, beginning of year	$8,798
Capitalization	1,300	1,400	1,700
Balance, end of year	8,273	8,798
Aflac U.S.
Deferred policy acquisition costs:
Balance, beginning of year	2,979	2,857
Capitalization	548	555
Amortization	-459	-433
Foreign currency translation and other	-6	0
Balance, end of year	3,062	2,979
Aflac Japan
Deferred policy acquisition costs:
Balance, beginning of year	5,819	6,801
Capitalization	790	893
Amortization	-649	-641
Foreign currency translation and other	-749	-1,234
Balance, end of year	$5,211	$5,819

DEFERRED_POLICY_ACQUISITION_CO4

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Advertising Expense (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Advertising Costs [Line Items]
Advertising expense	$229	$240	$254
Aflac Japan
Advertising Costs [Line Items]
Advertising expense	103	112	127
Aflac U.S.
Advertising Costs [Line Items]
Advertising expense	$126	$128	$127

DEFERRED_POLICY_ACQUISITION_CO5

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Depreciation and Other Amortization Expense (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred Policy Acquisition Costs and Insurance Expense Disclosure [Abstract]
Depreciation expense	$47	$56	$60
Other amortization expense	8	13	7
Total depreciation and other amortization expense	$55	$69	$67

DEFERRED_POLICY_ACQUISITION_CO6

DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Lease and Rental Expense (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Lease and Rental Expense [Line Items]
Lease and rental expense	$68	$66	$81
Aflac Japan
Lease and Rental Expense [Line Items]
Lease and rental expense	52	55	71
Aflac U.S.
Lease and Rental Expense [Line Items]
Lease and rental expense	15	10	9
All other
Lease and Rental Expense [Line Items]
Lease and rental expense	$1	$1	$1

POLICY_LIABILITIES_Additional_

POLICY LIABILITIES - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Liability for Future Policy Benefit, by Product Segment [Line Items]
Percentage of future policy benefits out of policy liabilities	78.00%
Percentage of unpaid policy claims out of policy liabilities	4.00%
Percentage of unearned premiums out of policy liabilities	11.00%
Percentage of other poliyholders' funds out of policy liabilities	7.00%
Percentage of advanced premiums to unearned premiums	80.00%	82.00%
Percentage of annuities to other policyholders' fund	98.00%	93.00%
Aflac Japan
Liability for Future Policy Benefit, by Product Segment [Line Items]
Weighted-average interest rates reflected in the consolidated statements of earnings for future policy benefits	3.80%	3.90%	4.00%
Aflac U.S.
Liability for Future Policy Benefit, by Product Segment [Line Items]
Weighted-average interest rates reflected in the consolidated statements of earnings for future policy benefits	5.70%	5.80%	6.00%

POLICY_LIABILITIES_Liability_f

POLICY LIABILITIES - Liability for Future Policy Benefits (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	65,646	69,136
Percentage of advanced premiums to unearned premiums	80.00%	82.00%
Aflac U.S.
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.70%	5.80%	6.00%
Aflac U.S. | Health insurance | 2012 - 2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	588	345
Aflac U.S. | Health insurance | 2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.75%
Interest Rates In 20 Years	4.75%
Liability amounts	276	243
Aflac U.S. | Health insurance | 2005-2010
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.50%
Interest Rates In 20 Years	5.50%
Liability amounts	2,951	2,897
Aflac U.S. | Health insurance | 1988-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	8.00%
Interest Rates In 20 Years	6.00%
Liability amounts	706	725
Aflac U.S. | Health insurance | 1986-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.00%
Interest Rates In 20 Years	6.00%
Liability amounts	1,293	1,301
Aflac U.S. | Health insurance | 1981-1986
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	183	190
Aflac U.S. | Health insurance | 1998-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	7.00%
Interest Rates In 20 Years	7.00%
Liability amounts	1,260	1,237
Aflac U.S. | Health insurance | Other years
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	21	22
Aflac U.S. | Life insurance | 1956-2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	452	396
Aflac Japan
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.80%	3.90%	4.00%
Aflac Japan | Health insurance | 2002-2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,900	3,370
Aflac Japan | Health insurance | 1974-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,449	3,889
Aflac Japan | Health insurance | 1998-2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Liability amounts	10,641	11,763
Aflac Japan | Health insurance | 1997-1999
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Liability amounts	2,461	2,842
Aflac Japan | Health insurance | 1994-1996
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,023	3,483
Aflac Japan | Health insurance | 1987 - 1994
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.50%
Interest Rates In 20 Years	5.50%
Liability amounts	14,394	16,727
Aflac Japan | Health insurance | 1985-1991
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	1,923	2,262
Aflac Japan | Health insurance | 1978-1984
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.50%
Interest Rates In 20 Years	5.50%
Liability amounts	2,260	2,699
Aflac Japan | Life insurance | 2013 - 2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	312	59
Aflac Japan | Life insurance | 2001-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,674	3,009
Aflac Japan | Life insurance | 2011-2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.00%
Interest Rates In 20 Years	2.00%
Liability amounts	2,298	1,584
Aflac Japan | Life insurance | 2009-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.25%
Interest Rates In 20 Years	2.25%
Liability amounts	1,890	1,648
Aflac Japan | Life insurance | 2005-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.50%
Interest Rates In 20 Years	2.50%
Liability amounts	1,214	1,211
Aflac Japan | Life insurance | 1985-2006
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.70%
Interest Rates In 20 Years	2.25%
Liability amounts	2,006	2,303
Aflac Japan | Life insurance | 2007-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.75%
Interest Rates In 20 Years	2.75%
Liability amounts	1,010	1,025
Aflac Japan | Life insurance | 1999-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Liability amounts	1,944	2,164
Aflac Japan | Life insurance | 1996-2009
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Liability amounts	633	721
Aflac Japan | Life insurance | 1994-1996
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	884	1,021
Health insurance | Aflac U.S. | 2012 - 2014 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Health insurance | Aflac U.S. | 2012 - 2014 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.75%
Interest Rates In 20 Years	3.75%
Health insurance | Aflac U.S. | 1981-1986 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.50%
Interest Rates In 20 Years	5.50%
Health insurance | Aflac U.S. | 1981-1986 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	7.00%
Interest Rates In 20 Years	6.50%
Health insurance | Aflac Japan | 2002-2014 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.25%
Interest Rates In 20 Years	1.25%
Health insurance | Aflac Japan | 2002-2014 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.50%
Interest Rates In 20 Years	2.50%
Health insurance | Aflac Japan | 1974-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.70%
Interest Rates In 20 Years	2.25%
Health insurance | Aflac Japan | 1974-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.75%
Interest Rates In 20 Years	2.75%
Health insurance | Aflac Japan | 1994-1996 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.00%
Interest Rates In 20 Years	4.00%
Health insurance | Aflac Japan | 1994-1996 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.50%
Interest Rates In 20 Years	4.50%
Health insurance | Aflac Japan | 1985-1991 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.25%
Interest Rates In 20 Years	5.25%
Health insurance | Aflac Japan | 1985-1991 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.75%
Interest Rates In 20 Years	5.50%
Life insurance | Aflac U.S. | 1956-2014 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Life insurance | Aflac U.S. | 1956-2014 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.00%
Interest Rates In 20 Years	6.00%
Life insurance | Aflac Japan | 2013 - 2014 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.50%
Interest Rates In 20 Years	1.50%
Life insurance | Aflac Japan | 2013 - 2014 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.75%
Interest Rates In 20 Years	1.75%
Life insurance | Aflac Japan | 2001-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.65%
Interest Rates In 20 Years	1.65%
Life insurance | Aflac Japan | 2001-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.85%
Interest Rates In 20 Years	1.85%
Life insurance | Aflac Japan | 1994-1996 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.00%
Interest Rates In 20 Years	4.00%
Life insurance | Aflac Japan | 1994-1996 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.50%
Interest Rates In 20 Years	4.50%

POLICY_LIABILITIES_Changes_in_

POLICY LIABILITIES - Changes in Liability for Unpaid Policy Claims (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Less claims paid during the year on claims incurred during:
Net balance, end of year	$3,630	$3,763
Total liability for unpaid policy claims	3,630	3,763	4,034
Health insurance
Liability for Unpaid Claims and Claims Expenses
Unpaid supplemental health claims, beginning of year	3,537	3,781	3,749
Less reinsurance recoverables	9	10	0
Net balance, beginning of year	3,528	3,771	3,749
Add claims incurred during the year related to:
Current year	6,866	7,215	8,013
Prior years	-301	-236	-173
Total incurred	6,565	6,979	7,840
Less claims paid during the year on claims incurred during:
Current year	4,532	4,834	5,453
Prior years	1,873	1,931	2,082
Total paid	6,405	6,765	7,535
Effect of foreign exchange rate changes on unpaid claims	-283	-457	-283
Net balance, end of year	3,405	3,528	3,771
Add reinsurance recoverables	7	9	10
Total liability for unpaid policy claims	3,412	3,537	3,781
Life insurance
Less claims paid during the year on claims incurred during:
Total liability for unpaid policy claims	$218	$226	$253

REINSURANCE_Additional_Informa

REINSURANCE Additional Information (Detail) (Aflac Japan, USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Closed Medical Block - Tranche Two
Effects of Reinsurance [Line Items]
Reinsurance ceded percentage	16.70%
Closed Medical Block - Tranche One
Effects of Reinsurance [Line Items]
Reinsurance ceded percentage	33.30%
Closed medical block
Effects of Reinsurance [Line Items]
Reinsurance deferred profit liability	820
Reinsurance recoverables	838
Reinsurance assumed percentage	8.35%

REINSURANCE_Effect_of_Reinsura

REINSURANCE Effect of Reinsurance on Premiums and Benefits and Claims (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effects of Reinsurance [Line Items]
Direct premiums earned									$19,412	$20,233	$22,167
Ceded premiums									-350	-110	-33
Assumed premiums from other companies									10	12	14
Net premium income	4,489	4,841	4,888	4,854	4,910	5,028	5,013	5,184	19,072	20,135	22,148
Direct benefits and claims									13,235	13,903
Assumed benefits and claims from other companies									5	8
Benefits and claims, net									12,937	13,813	15,330
All other
Effects of Reinsurance [Line Items]
Ceded premiums									-39	-34
Ceded benefits and claims									-27	-31
Aflac Japan
Effects of Reinsurance [Line Items]
Net premium income									13,861	14,982	17,151
Benefits and claims, net									10,084	10,924	12,496
Aflac Japan | Closed medical block
Effects of Reinsurance [Line Items]
Ceded premiums									-311	-76
Ceded benefits and claims									($276)	($67)

NOTES_PAYABLE_Additional_Infor

NOTES PAYABLE - Additional Information (Detail)

12 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

Dec. 31, 2014

Feb. 29, 2012

Jul. 31, 2011

Nov. 30, 2014

Nov. 30, 2014

Dec. 31, 2014

Jun. 30, 2013

Jun. 30, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Jul. 31, 2011

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Feb. 29, 2012

Jul. 31, 2012

Feb. 29, 2012

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Feb. 29, 2012

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Oct. 31, 2012

Oct. 31, 2012

Sep. 30, 2012

Sep. 30, 2012

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2009

Dec. 31, 2014

Dec. 31, 2013

31-May-09

Dec. 31, 2014

Dec. 31, 2013

Sep. 30, 2006

Dec. 31, 2009

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Oct. 31, 2014

Dec. 31, 2014

series

series

3.625% senior notes due November 2024

3.625% senior notes due November 2024

3.625% senior notes due November 2024

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due June 2023

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

Senior Notes

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

Yen Denominated Samurai Notes

4.00% senior notes due February 2022

4.00% senior notes due February 2022

4.00% senior notes due February 2022

4.00% senior notes due February 2022

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

6.45% senior notes due August 2040

6.45% senior notes due August 2040

6.45% senior notes due August 2040

3.45% senior notes due August 2015

3.45% senior notes due August 2015

3.45% senior notes due August 2015

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.90% senior notes due December 2039

8.50% senior notes due May 2019

8.50% senior notes due May 2019

8.50% senior notes due May 2019

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

Notes Payable

Notes Payable

Line of credit

Line of credit

Fifty billion yen line of credit

Fifty billion yen line of credit

One hundred million dollar line of credit

One hundred million dollar line of credit

USD ($)

JPY (¥)

USD ($)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

USD ($)

USD ($)

Debt Instrument [Line Items]

Line of credit facility term

364-day

Notes payable, interest rate

3.63%

3.63%

3.63%

3.63%

3.63%

3.63%

3.63%

1.47%

1.84%

1.84%

1.84%

1.30%

3.00%

3.00%

2.65%

2.65%

2.65%

2.65%

2.65%

4.00%

4.00%

4.00%

4.00%

5.50%

5.50%

5.50%

5.50%

5.50%

5.50%

6.45%

6.45%

3.45%

3.45%

6.90%

6.90%

8.50%

8.50%

2.26%

2.26%

Debt Instrument, Term

10 years

10 years

10 years

10 years

5 years

5 years

5 years

5 years

10 years

10 years

40 years

40 years

30 years

5 years

30 years

10 years

10 years

Debt Instrument, redemption, description

These notes are redeemable at our 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 treasury rate plus 20 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.

These notes are redeemable at our 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 treasury rate plus 20 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.

These notes are redeemable at our 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 treasury rate plus 20 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.

These notes are redeemable at our 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 treasury rate plus 20 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.

Debt instrument effective principal amount after cross currency swap

¥ 85,300,000,000

¥ 69,800,000,000

¥ 30,900,000,000

¥ 27,000,000,000

¥ 3,900,000,000

¥ 35,300,000,000

Principal payments under debt obligations

1,400,000,000

Notes payable, principal amount

750,000,000

750,000,000

700,000,000

700,000,000

28,700,000,000

28,700,000,000

15,800,000,000

15,800,000,000

15,800,000,000

5,500,000,000

5,500,000,000

5,500,000,000

5,000,000,000

5,000,000,000

750,000,000

250,000,000

400,000,000

400,000,000

50,000,000,000

350,000,000

350,000,000

50,000,000

450,000,000

500,000,000

450,000,000

300,000,000

400,000,000

850,000,000

10,000,000,000

8,000,000,000

8,000,000,000

Minimum prinicipal amount outstanding following partial redemption

25,000,000

Number of series of senior notes issued through a U.S. public debt offering (in series)

2

3

Notes payable, effective interest rate

1.00%

1.00%

1.50%

1.50%

1.48%

1.22%

1.22%

2.07%

2.07%

4.42%

4.42%

4.41%

4.41%

Derivative, Description of Terms

P5Y

P5Y

P5Y

P5Y

Extinguishment of notes

2,000,000,000

Gain on extinguishment of debt

600,000,000

Line of credit facility, maximum borrowing capacity

50,000,000,000

100,000,000

100,000,000

Line of Credit Facility, Expiration Period Description

This credit agreement will expire on the earlier of March 29, 2018, or the date of termination of the commitments upon an event of default as defined in the agreement.

Line of credit facility, interest rate description

Borrowings will bear interest at LIBOR plus the applicable margin of 1.125%

Borrowings will bear interest at LIBOR plus the applicable margin of 1.125%

Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period.

Line of credit facility, commitment fee percentage

0.13%

0.13%

Line of credit facility, amount outstanding

0

0

Notes payable, debt default, amount

$0

$0

$0

$0

NOTES_PAYABLE_Summary_of_Notes

NOTES PAYABLE - Summary of Notes Payable (Detail)

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2012

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

31-May-09

Dec. 31, 2014

Dec. 31, 2013

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Jun. 30, 2013

Dec. 31, 2014

Nov. 30, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2009

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Oct. 31, 2012

Sep. 30, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Sep. 30, 2006

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

USD ($)

USD ($)

3.45% senior notes due August 2015

3.45% senior notes due August 2015

3.45% senior notes due August 2015

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

8.50% senior notes due May 2019

8.50% senior notes due May 2019

8.50% senior notes due May 2019

4.00% senior notes due February 2022

4.00% senior notes due February 2022

4.00% senior notes due February 2022

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due November 2024

3.625% senior notes due November 2024

3.625% senior notes due November 2024

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.45% senior notes due August 2040

6.45% senior notes due August 2040

6.45% senior notes due August 2040

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

Capitalized lease obligations

Capitalized lease obligations

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

USD ($)

Debt Instrument [Line Items]

Notes payable

$5,282,000,000

$4,897,000,000

$300,000,000

$300,000,000

$653,000,000

[1]

$655,000,000

[1]

$850,000,000

$850,000,000

$350,000,000

[2]

$349,000,000

[2]

$700,000,000

$700,000,000

$749,000,000

[2]

$0

$397,000,000

[2]

$396,000,000

[2]

$448,000,000

[2]

$448,000,000

[2]

$500,000,000

$500,000,000

$66,000,000

$76,000,000

$0

$272,000,000

$131,000,000

$150,000,000

$0

$52,000,000

$83,000,000

$95,000,000

$41,000,000

$48,000,000

$14,000,000

$6,000,000

Notes payable, principal amount

$300,000,000

$400,000,000

$250,000,000

$400,000,000

$850,000,000

$350,000,000

$350,000,000

$700,000,000

$700,000,000

$750,000,000

$750,000,000

$400,000,000

$450,000,000

$500,000,000

$50,000,000

$450,000,000

¥ 8,000,000,000

¥ 8,000,000,000

¥ 10,000,000,000

¥ 28,700,000,000

¥ 28,700,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 10,000,000,000

¥ 10,000,000,000

¥ 5,000,000,000

¥ 5,000,000,000

Notes payable, interest rate

3.45%

3.45%

2.65%

2.65%

2.65%

2.65%

8.50%

8.50%

4.00%

4.00%

4.00%

3.63%

3.63%

3.63%

3.63%

3.63%

6.90%

6.90%

6.45%

6.45%

5.50%

5.50%

5.50%

5.50%

2.26%

2.26%

2.26%

2.26%

1.47%

1.47%

1.84%

1.84%

1.84%

1.84%

1.84%

1.30%

1.30%

3.60%

3.60%

3.60%

3.60%

3.00%

3.00%

3.00%

3.00%

[1]

Principal amount plus an issuance premium that is being amortized over the life of the notes

[2]

Principal amount net of an issuance discount that is being amortized over the life of the notes

NOTES_PAYABLE_Aggregate_Contra

NOTES PAYABLE - Aggregate Contractual Maturities of Notes Payable (Detail) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Debt Instrument [Line Items]
2015	$428
2016	201
2017	653
2018	2
2019	851
Thereafter	3,150
Total	5,285
Long-term debt
Debt Instrument [Line Items]
2015	424
2016	197
2017	650
2018	0
2019	850
Thereafter	3,150
Total	5,271
Capitalized lease obligations
Debt Instrument [Line Items]
2015	4
2016	4
2017	3
2018	2
2019	1
Thereafter	0
Total	$14

NOTES_PAYABLE_Summary_of_Notes1

NOTES PAYABLE Summary of Notes Payable Parenthetical (Details)

Dec. 31, 2014

Dec. 31, 2013

31-May-09

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2009

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2012

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Oct. 31, 2012

Sep. 30, 2012

Dec. 31, 2014

Dec. 31, 2013

Sep. 30, 2006

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Jun. 30, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Nov. 30, 2014

8.50% senior notes due May 2019

8.50% senior notes due May 2019

8.50% senior notes due May 2019

6.45% senior notes due August 2040

6.45% senior notes due August 2040

6.45% senior notes due August 2040

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.90% senior notes due December 2039

3.45% senior notes due August 2015

3.45% senior notes due August 2015

3.45% senior notes due August 2015

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

4.00% senior notes due February 2022

4.00% senior notes due February 2022

4.00% senior notes due February 2022

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due June 2023

1.87% yen-denominated Samurai notes paid June 2012

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

3.625% senior notes due November 2024

3.625% senior notes due November 2024

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

USD ($)

USD ($)

Debt Instrument [Line Items]

Notes payable, interest rate

8.50%

8.50%

6.45%

6.45%

6.90%

6.90%

3.45%

3.45%

2.65%

2.65%

2.65%

2.65%

4.00%

4.00%

4.00%

5.50%

5.50%

5.50%

5.50%

2.26%

2.26%

1.47%

3.63%

3.63%

3.63%

1.84%

1.84%

1.84%

1.30%

3.60%

3.60%

3.00%

3.00%

3.63%

3.63%

Notes payable, principal amount

$850,000,000

$450,000,000

$400,000,000

$300,000,000

$400,000,000

$250,000,000

$400,000,000

$350,000,000

$350,000,000

$500,000,000

$50,000,000

$450,000,000

¥ 8,000,000,000

¥ 8,000,000,000

¥ 10,000,000,000

¥ 28,700,000,000

¥ 28,700,000,000

$700,000,000

$700,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 10,000,000,000

¥ 10,000,000,000

¥ 5,000,000,000

¥ 5,000,000,000

$750,000,000

$750,000,000

INCOME_TAXES_Additional_Inform

INCOME TAXES - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Apr. 02, 2012	Jan. 01, 2015
Income Taxes [Line Items]
Unrecognized tax benefit, deductibility highly certain, timing uncertain	$307	$327
Japan Tax Rate					33.30%
Deferred tax expense (benefit)	461	422	620
The expected U.S. tax rate	35.00%	35.00%
Income tax expense (benefit) related to items of other comprehensive income (loss)	1,803	-581	1,078
Non-life operating loss carryforwards, limitations	only 35% of non-life operating losses can be offset against life insurance taxable income each year
Tax credit carryforward, amount	0
Unrecognized tax benefits, permanent uncertainties	2
Unrecognized tax benefits, interest and penalties expense	11	11	7
Unrecognized tax benefits, accrued interest and penalties	30	26
Capital loss carryforwards	73
Expiring in 2031
Income Taxes [Line Items]
Non-life operating loss carryforwards	18
Expiring in 2032
Income Taxes [Line Items]
Non-life operating loss carryforwards	17
Expiring in 2033
Income Taxes [Line Items]
Non-life operating loss carryforwards	2
Expiring in 2034
Income Taxes [Line Items]
Non-life operating loss carryforwards	1
Change In Income Tax Rate
Income Taxes [Line Items]
Japan Tax Rate						30.80%
Aflac Japan
Income Taxes [Line Items]
Deferred tax expense (benefit)	125	299	950
Aflac Japan | Dollar denominated investment portfolio
Income Taxes [Line Items]
Income tax expense (benefit) related to items of other comprehensive income (loss)		614	492
Effective income tax rate excluding income tax expense (benefit) related to Aflac Japan's dollar-denominated portfolio		31.00%	32.00%
Aflac Japan | Foreign Tax Credits
Income Taxes [Line Items]
Deferred tax expense (benefit)			374	-744
Aflac U.S.
Income Taxes [Line Items]
Deferred tax expense (benefit)	336	123	-330
Aflac U.S. | Foreign Tax Credits
Income Taxes [Line Items]
Deferred tax expense (benefit)			($374)	$744

INCOME_TAXES_Components_of_Inc

INCOME TAXES - Components of Income Tax Expense (Benefit) Applicable to Pretax Earnings (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Provision of Income Taxes [Line Items]
Current									$1,079	$1,236	$816
Deferred									461	422	620
Total income tax expense	372	368	428	372	353	367	469	469	1,540	1,658	1,436
Aflac U.S.
Reconciliation of Provision of Income Taxes [Line Items]
Current									84	302	303
Deferred									336	123	-330
Total income tax expense									420	425	-27
Aflac Japan
Reconciliation of Provision of Income Taxes [Line Items]
Current									995	934	513
Deferred									125	299	950
Total income tax expense									$1,120	$1,233	$1,463

INCOME_TAXES_Principal_Reasons

INCOME TAXES - Principal Reasons for Differences and Related Tax Effects where Income Tax Expense Varies from Amount Computed by Applying Expected United States Tax Rate of Thirty Five Percent to Pretax Earnings (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Income taxes based on U.S. statutory rates									$1,572	$1,685	$1,506
Utilization of foreign tax credit									-32	-37	-53
Nondeductible expenses									5	6	8
Other, net									-5	4	-25
Total income tax expense	$372	$368	$428	$372	$353	$367	$469	$469	$1,540	$1,658	$1,436

INCOME_TAXES_Total_Income_Tax_

INCOME TAXES - Total Income Tax Expense (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Statements of earnings	$372	$368	$428	$372	$353	$367	$469	$469	$1,540	$1,658	$1,436
Other comprehensive income (loss):
Unrealized foreign currency translation gains (losses) during period									-419	253	363
Unrealized gains (losses) on investment securities:
Unrealized holding gains (losses) on investment securities during period									2,237	-904	904
Reclassification adjustment for realized (gains) losses on investment securities included in net earnings									19	19	-174
Unrealized gains (losses) on derivatives during period									-3	-4	-8
Pension liability adjustment during period									-31	55	-7
Total income tax expense (benefit) related to items of other comprehensive income (loss)									1,803	-581	1,078
Additional paid-in capital (exercise of stock options)									-7	-8	-12
Total income taxes									$3,336	$1,069	$2,502

INCOME_TAXES_Income_Tax_Effect

INCOME TAXES - Income Tax Effects of Temporary Differences that Gave Rise to Deferred Income Tax Assets and Liabilities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Deferred income tax liabilities:
Deferred policy acquisition costs	$2,209	$2,406
Unrealized gains on investment securities	2,584	533
Premiums receivable	139	134
Policy benefit reserves	1,376	1,451
Depreciation	51	54
Other	20	22
Total deferred income tax liabilities	6,379	4,600
Deferred income tax assets:
Other basis differences in investment securities	1,331	1,129
Unfunded retirement benefits	16	16
Other accrued expenses	4	23
Policy and contract claims	99	111
Foreign currency loss on Japan branch	327	189
Deferred compensation	226	182
Capital loss carryforwards	26	514
Total deferred income tax assets	2,029	2,164
Deferred Tax Assets, Net, Noncurrent	-4,350	-2,436
Deferred Tax Liabilities, Net, Current	943	1,282
Total income tax liability	$5,293	$3,718

INCOME_TAXES_Reconciliation_of

INCOME TAXES - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of year	$328	$401
Additions for tax positions of prior years	2	1
Reductions for tax positions of prior years	-21	-74
Balance, end of year	$309	$328

SHAREHOLDERS_EQUITY_Additional

SHAREHOLDERS' EQUITY - Additional Information (Detail)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders Equity Note [Line Items]
Common stock, voting rights	are generally entitled to one vote per share until they have been held by the same beneficial owner for a continuous period of 48 months, at which time they become entitled to 10 votes per share.
Voting rights, votes per share	1
Remaining common stock available for purchase under share repurchase authorizations	29.6
The expected U.S. tax rate	35.00%	35.00%
Share repurchase program
Stockholders Equity Note [Line Items]
Common stock, share repurchase	19.7	13.2	1.9
Share Held For Continuous Forty Eight Month Period
Stockholders Equity Note [Line Items]
Voting rights, votes per share	10

SHAREHOLDERS_EQUITY_Reconcilia

SHAREHOLDERS' EQUITY - Reconciliation of Number of Shares of Common Stock (Detail)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Common Stock Issued [Roll Forward]
Balance, beginning of period	667,046	665,239	663,639
Exercise of stock options and issuance of restricted shares	1,086	1,807	1,600
Balance, end of period	668,132	667,046	665,239
Treasury Stock [Roll Forward]
Balance, beginning of period	207,633	197,453	197,329
Exercise of stock options	-1,236	-3,281	-2,476
Balance, end of period	225,687	207,633	197,453
Shares outstanding, end of period	442,445	459,413	467,786
Treasury Stock
Treasury Stock [Roll Forward]
Stock acquired in open market, shares	19,660	13,212	1,948
Other purchases	157	222	360
Shares issued to AFL Stock Plan	-1,251	-1,365	-1,670
Exercise of stock options	-391	-1,734	-387
Other dispositions	-121	-155	-127

SHAREHOLDERS_EQUITY_AntiDiluti

SHAREHOLDERS' EQUITY - Anti-Dilutive Share-Based Awards Excluded from Calculation of Diluted Earnings Per Share (Detail)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders' Equity Note [Abstract]
Anti-dilutive share-based awards	1,215	2,198	5,880

SHAREHOLDERS_EQUITY_WeightedAv

SHAREHOLDERS' EQUITY - Weighted-Average Shares Used in Calculating Earnings Per Share (Details)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders' Equity Note [Abstract]
Weighted-average outstanding shares used for calculating basic EPS	451,204	464,502	466,868
Dilutive effect of share-based awards	2,796	2,906	2,419
Weighted-average outstanding shares used for calculating diluted EPS	454,000	467,408	469,287

SHAREHOLDERS_EQUITY_Changes_in

SHAREHOLDERS' EQUITY - Changes in Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	($563)	[1]	$2,715	[1]
Other comprehensive income loss before reclassifications net of tax	2,578	[1]	-3,247	[1]
Amounts reclassified from accumulated other comprehensive income net of tax	-36	[1]	-31	[1]
Other comprehensive income (loss), net of income taxes	2,542	[1]	-3,278	[1]	750
Balance, end of period	1,979	[1]	-563	[1]	2,715	[1]
Unrealized foreign currency translation gains (losses)
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	-1,505	[1]	333	[1]
Other comprehensive income loss before reclassifications net of tax	-1,036	[1]	-1,833	[1]
Amounts reclassified from accumulated other comprehensive income net of tax	0	[1]	-5	[1]
Other comprehensive income (loss), net of income taxes	-1,036	[1]	-1,838	[1]
Balance, end of period	-2,541	[1]	-1,505	[1]
Unrealized gains (losses) on investment securities
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	1,035	[1]	2,570	[1]
Other comprehensive income loss before reclassifications net of tax	3,672	[1]	-1,499	[1]
Amounts reclassified from accumulated other comprehensive income net of tax	-35	[1]	-36	[1]
Other comprehensive income (loss), net of income taxes	3,637	[1]	-1,535	[1]
Balance, end of period	4,672	[1]	1,035	[1]
Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	-12	[1]	-5	[1]
Other comprehensive income loss before reclassifications net of tax	-14	[1]	-7	[1]
Amounts reclassified from accumulated other comprehensive income net of tax	0	[1]	0	[1]
Other comprehensive income (loss), net of income taxes	-14	[1]	-7	[1]
Balance, end of period	-26	[1]	-12	[1]
Pension liability adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	-81	[1]	-183	[1]
Other comprehensive income loss before reclassifications net of tax	-44	[1]	92	[1]
Amounts reclassified from accumulated other comprehensive income net of tax	-1	[1]	10	[1]
Other comprehensive income (loss), net of income taxes	-45	[1]	102	[1]
Balance, end of period	($126)	[1]	($81)	[1]
[1]	All amounts in the table above are net of tax.

SHAREHOLDERS_EQUITY_Reclassifi

SHAREHOLDERS' EQUITY - Reclassifications Out of Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Sales and redemptions									$215		$262		$474
Other-than-temporary impairment losses realized									-31	[1]	-199	[1]	-977	[1]
Total before tax	1,075	1,074	1,238	1,104	1,028	1,069	1,358	1,361	4,491		4,816		4,302
Income Tax (Expense) Benefit	-372	-368	-428	-372	-353	-367	-469	-469	-1,540		-1,658		-1,436
Net of tax									2,951		3,158		2,866
The expected U.S. tax rate									35.00%		35.00%
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net of tax									36		31
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on investment securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Sales and redemptions									57		255
Other-than-temporary impairment losses realized									-3		-199
Total before tax									54		56
Income Tax (Expense) Benefit									-19	[2]	-20	[2]
Net of tax									35		36
Reclassification out of Accumulated Other Comprehensive Income | Pension liability adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Acquisition and operating expense, actuarial gains (losses)									-15	[3]	-19	[3]
Acquisition and operating expenses, prior service (cost) credit									17	[3]	4	[3]
Income Tax (Expense) Benefit									-1	[2]	5	[2]
Net of tax									1		-10
Reclassification out of Accumulated Other Comprehensive Income | Unrealized foreign currency translation gains (losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Sales and redemptions											7
Income Tax (Expense) Benefit											-2	[2]
Net of tax											$5
[1]	Includes $45 and $597 for the years ended DecemberB 31, 2013 and 2012, respectively, for credit-related impairments; $26 and $27 for the years ended DecemberB 31, 2013 and 2012, respectively, for impairments due to severity and duration of decline in fair value; and $31, $128 and $353 for the years ended DecemberB 31, 2014, 2013 and 2012, respectively, from change in intent to sell securities
[2]	Based on 35% tax rate
[3]	These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).

SHAREBASED_COMPENSATION_Additi

SHARE-BASED COMPENSATION - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of long-term incentive compensation plans	2
Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Grant Date Fair Value	$16.24	14.25	16.84
Closing common stock price	$61.09
Aggregate intrinsic value of stock options outstanding	$116
Options Outstanding - Weighted-Average Remaining Term (Yrs)	4 years 6 months
Aggregate intrinsic value of stock options exercisable	103
Weighted-average remaining term of stock options exercisable (in years)	3 years 7 months 6 days
Stock Option Plan Effective Until February 2007 Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, term (in years)	10 years
Second Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Stock option plan, vesting period	3 years
Shares available for future grants under the long-term incentive plan	11,200,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	45
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,880,000	1,671,000	1,363,000	1,350,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 2 months 12 days
Performance Based Vesting Condition Member | Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	$20
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	849,000

SHAREBASED_COMPENSATION_Expens

SHARE-BASED COMPENSATION - Expense Recognized in Connection with Share-Based Awards (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Earnings before income taxes	$1,075	$1,074	$1,238	$1,104	$1,028	$1,069	$1,358	$1,361	$4,491	$4,816	$4,302
Net earnings									2,951	3,158	2,866
Net earnings per share:
Basic (in dollars per share)	$1.57	$1.56	$1.79	$1.61	$1.46	$1.51	$1.91	$1.91	$6.54	$6.80	$6.14
Diluted (in dollars per share)	$1.57	$1.56	$1.78	$1.60	$1.45	$1.50	$1.90	$1.90	$6.50	$6.76	$6.11
Share Based Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Earnings from continuing operations									41	37	37
Earnings before income taxes									41	37	37
Net earnings									$28	$25	$26
Net earnings per share:
Basic (in dollars per share)									$0.06	$0.05	$0.06
Diluted (in dollars per share)									$0.06	$0.05	$0.06

SHAREBASED_COMPENSATION_Assump

SHARE-BASED COMPENSATION - Assumptions Used in Valuing Options Granted (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected term (years)	6 years 3 months 18 days	6 years 7 months 6 days	6 years 6 months
Expected volatility	30.00%	34.00%	38.00%
Annual forfeiture rate	2.70%	1.60%	1.60%
Risk-free interest rate	2.80%	1.80%	2.10%
Dividend yield	2.30%	2.60%	1.30%

SHAREBASED_COMPENSATION_Stock_

SHARE-BASED COMPENSATION - Stock Option Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock Option Shares
Beginning Balance	9,980	12,737	14,563
Granted	678	703	784
Canceled	-115	-179	-134
Exercised	-1,236	-3,281	-2,476
Ending Balance	9,307	9,980	12,737
Weighted-Average Exercise Price Per Share
Beginning Balance	$47.03	$45	$42.76
Granted	$61.81	$52.86	$47.25
Canceled	$52.01	$44.79	$48.59
Exercised	$41.04	$40.52	$32.27
Ending Balance	$48.84	$47.03	$45

SHAREBASED_COMPENSATION_Shares

SHARE-BASED COMPENSATION - Shares Exercisable (Detail)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares exercisable, end of year	7,497	8,042	10,635

SHAREBASED_COMPENSATION_Stock_1

SHARE-BASED COMPENSATION - Stock Options Outstanding and Exercisable (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$14.99
Range of Exercise Prices Per Share - Upper Range	$67.67
Options Outstanding - Stock Option Shares	9,307	9,980	12,737	14,563
Options Outstanding - Weighted-Average Remaining Term (Yrs)	4 years 6 months
Options Outstanding - Weighted-Average Exercise Price Per Share	$48.84	$47.03	$45	$42.76
Options Exercisable - Stock Option Shares	7,497	8,042	10,635
Options Exercisable - Weighted-Average Exercise Price Per Share	$47.51
$14.99 - $43.07
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$14.99
Range of Exercise Prices Per Share - Upper Range	$43.07
Options Outstanding - Stock Option Shares	2,028
Options Outstanding - Weighted-Average Remaining Term (Yrs)	3 years 9 months 18 days
Options Outstanding - Weighted-Average Exercise Price Per Share	$34.46
Options Exercisable - Stock Option Shares	1,945
Options Exercisable - Weighted-Average Exercise Price Per Share	$34.20
$43.28 - $47.25
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$43.28
Range of Exercise Prices Per Share - Upper Range	$47.25
Options Outstanding - Stock Option Shares	2,144
Options Outstanding - Weighted-Average Remaining Term (Yrs)	3 years 1 month 6 days
Options Outstanding - Weighted-Average Exercise Price Per Share	$45.93
Options Exercisable - Stock Option Shares	2,046
Options Exercisable - Weighted-Average Exercise Price Per Share	$45.93
$47.33 - $51.91
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$47.33
Range of Exercise Prices Per Share - Upper Range	$51.91
Options Outstanding - Stock Option Shares	1,883
Options Outstanding - Weighted-Average Remaining Term (Yrs)	5 years 4 months 24 days
Options Outstanding - Weighted-Average Exercise Price Per Share	$48.97
Options Exercisable - Stock Option Shares	1,109
Options Exercisable - Weighted-Average Exercise Price Per Share	$48.86
$52.14 - $61.81
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$52.14
Range of Exercise Prices Per Share - Upper Range	$61.81
Options Outstanding - Stock Option Shares	2,479
Options Outstanding - Weighted-Average Remaining Term (Yrs)	4 years 6 months
Options Outstanding - Weighted-Average Exercise Price Per Share	$58.65
Options Exercisable - Stock Option Shares	2,296
Options Exercisable - Weighted-Average Exercise Price Per Share	$58.79
$61.84 - $67.67
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices Per Share - Lower Range	$61.84
Range of Exercise Prices Per Share - Upper Range	$67.67
Options Outstanding - Stock Option Shares	773
Options Outstanding - Weighted-Average Remaining Term (Yrs)	8 years 6 months
Options Outstanding - Weighted-Average Exercise Price Per Share	$62.85
Options Exercisable - Stock Option Shares	101
Options Exercisable - Weighted-Average Exercise Price Per Share	$64.63

SHAREBASED_COMPENSATION_Summar

SHARE-BASED COMPENSATION - Summary of Stock Option Activity (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total intrinsic value of options exercised	$25	$66	$41
Cash received from options exercised	39	113	35
Tax benefit realized as a result of options exercised and restricted stock releases	$17	$30	$24

SHAREBASED_COMPENSATION_Restri

SHARE-BASED COMPENSATION - Restricted Stock Activity (Detail) (Restricted stock, USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted stock
Shares
Beginning balance	1,671	1,363	1,350
Granted	584	782	637
Canceled	-27	-56	-56
Vested	-348	-418	-568
Ending Balance	1,880	1,671	1,363
Weighted-Average Grant-Date Fair Value Per Share
Beginning balance	$52.12	$50.19	$40.92
Granted	$62.12	$52.77	$48.18
Canceled	$52.66	$48.63	$48.22
Vested	$56.95	$47.49	$26.13
Ending Balance	$54.33	$52.12	$50.19

STATUTORY_ACCOUNTING_AND_DIVID2

STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Additional Information (Detail)

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

Aflac

Aflac

Aflac

Aflac

Aflac

Aflac Japan

Aflac Japan

2014 profit repatriation

2014 profit repatriation

Foreign currency forwards

Foreign currency forwards

Foreign currency forwards and options

Foreign currency forwards and options

USD ($)

USD ($)

USD ($)

Separate Account Funding Agreements

Separate Account Funding Agreements

USD ($)

USD ($)

USD ($)

USD ($)

December 2014 profit repatriation

Profit repatriation

July 2014 profit repatriation

December 2014 profit repatriation

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

Statutory Accounting Practices [Line Items]

Capital and surplus, statutory accounting practices of the state or country basis

$10,839,000,000

$9,630,000,000

$5,600,000,000

$4,200,000,000

Guaranteed separate account funding agreements, unrealized gain (loss)

0

35,000,000

Statutory Accounting Practices, Statutory Capital and Surplus Required

1,200,000,000

Net Income, Nebraska state basis

2,400,000,000

2,400,000,000

2,300,000,000

Amount available for dividend distribution without prior approval from regulatory agency

2,400,000,000

Dividends declared

1,500,000,000

Net Derivatives Notional Amount

23,662,000,000

22,475,000,000

50,000,000,000

157,500,000,000

52,500,000,000

50,000,000,000

Foreign Currency Transaction Gain (Loss), before Tax

$7,000,000

$45,000,000

STATUTORY_ACCOUNTING_AND_DIVID3

STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Reconciliation of Capital and Surplus Between Sap and Practices Permitted by the State of Nebraska (Detail) (Aflac, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statutory Accounting Practices [Line Items]
Capital and surplus, Nebraska state basis	$10,839	$9,630
Capital and surplus, NAIC basis	10,803	9,624
Refundable lease deposits - Japan
Statutory Accounting Practices [Line Items]
State permitted practice amount	-36	-41
Separate Account Funding Agreements
Statutory Accounting Practices [Line Items]
State permitted practice amount	$0	$35

STATUTORY_ACCOUNTING_AND_DIVID4

STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Profits Repatriated by Aflac Japan to Aflac U.S. (Detail)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012
	USD ($)	JPY (¥)	USD ($)	JPY (¥)	USD ($)	JPY (¥)
Statutory Accounting Practices Disclosure [Abstract]
Profit repatriation	$1,704	¥ 181,400	$771	¥ 76,800	$422	¥ 33,100

BENEFIT_PLANS_Additional_Infor

BENEFIT PLANS - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Oct. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amount of years left to meet rule of 80 for active employees 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
Transition obligation		$0
Percentage of matching contributions by the Company to employee's contributions to 401(k) plan		50.00%	50.00%	50.00%
Matching 401(k) plan contributions included in acquisition and operating expenses		7	5	5
Shares of employer-issued common stock held for plan participants by plan trustee (in millions)		2
Non-Elective Defined Contribution Percentage of Employee Compensation		2.00%
Lower Limit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Health care plan, retirement age for eligibility, (in years)			55 years
Health care plan, number of years of service for eligibility			15 years
Health care plan, retirement age and years of service combined years for eligibility			80 years
Upper Limit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of employee's compensation eligible for Company match in 401(k) plan		6.00%
Japanese Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Amendments		0	0
Discount rate - benefit obligations		1.75%	2.25%	2.25%
AA corporate bonds average duration		20 years
Prior service cost (credit)		0	0	0
Transition obligation		0	1
Defined benefit plan, future amortization of actuarial losses		1
Defined benefit plan, expected contributions to the plan in 2015		19
U.S. Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Amendments		0	-4
Discount rate - benefit obligations		4.50%	4.75%	4.25%
AA corporate bonds average duration		17 years
Prior service cost (credit)		0	-4	-1
Transition obligation		0	0
Defined benefit plan, future amortization of actuarial losses		15
Defined benefit plan, expected contributions to the plan in 2015		10
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Amendments	-51	0	-51
Plan amendment remaining amortization period	3 years
Discount rate - benefit obligations	4.75%	4.50%	4.75%	4.25%
Prior service cost (credit)		0	-51	2
Transition obligation		0	0
Defined benefit plan, future amortization of actuarial losses		2
Defined benefit plan, future amortization of prior service cost (credit)		-17
Associate Stock Bonus Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred policy acquisition costs, amount attributable to stock bonus plan		$36	$38	$38

BENEFIT_PLANS_Reconciliation_o

BENEFIT PLANS - Reconciliation of Funded Status of Basic Employee Defined-Benefit Pension Plans (Detail) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Oct. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Amounts recognized in accumulated other comprehensive income:
Transition obligation		$0
Japanese Pension Plan
Projected benefit obligation:
Benefit obligation, beginning of year		270		313
Service cost		15		16		18
Interest cost		9		10		7
Plan amendments		0		0
Actuarial (gain) loss		21		-3
Benefits and expenses paid		-9		-8
Effect of foreign exchange rate changes		-39		-58
Benefit obligation, end of year		267		270		313
Plan assets:
Fair value of plan assets, beginning of year		182		187
Actual return on plan assets		12		13
Employer contributions		24		26
Benefits and expenses paid		-9		-8
Effect of foreign exchange rate changes		-26		-36
Fair value of plan assets, end of year		183		182		187
Funded status of the plans		-84	[1]	-88	[1]
Amounts recognized in accumulated other comprehensive income:
Net actuarial (gain) loss		40		33
Prior service (credit) cost		-2		-2
Transition obligation		0		1
Total included in accumulated other comprehensive income		38		32
Accumulated benefit obligation		235		239
U.S. Pension Plan
Projected benefit obligation:
Benefit obligation, beginning of year		601		613
Service cost		20		22		18
Interest cost		38		23		24
Plan amendments		0		-4
Actuarial (gain) loss		74		-37
Benefits and expenses paid		-16		-16
Effect of foreign exchange rate changes		0		0
Benefit obligation, end of year		717		601		613
Plan assets:
Fair value of plan assets, beginning of year		313		261
Actual return on plan assets		26		39
Employer contributions		18		29
Benefits and expenses paid		-16		-16
Effect of foreign exchange rate changes		0		0
Fair value of plan assets, end of year		341		313		261
Funded status of the plans		-376	[1]	-288	[1]
Amounts recognized in accumulated other comprehensive income:
Net actuarial (gain) loss		167		111
Prior service (credit) cost		-4		-4
Transition obligation		0		0
Total included in accumulated other comprehensive income		163		107
Accumulated benefit obligation		611		514
Other Postretirement Benefit Plans, Defined Benefit
Projected benefit obligation:
Benefit obligation, beginning of year		46		98
Service cost		1		5		6
Interest cost		2		3		4
Plan amendments	-51	0		-51
Actuarial (gain) loss		-3		-7
Benefits and expenses paid		-2		-2
Effect of foreign exchange rate changes		0		0
Benefit obligation, end of year		44		46		98
Plan assets:
Fair value of plan assets, beginning of year		0		0
Actual return on plan assets		0		0
Employer contributions		2		2
Benefits and expenses paid		-2		-2
Effect of foreign exchange rate changes		0		0
Fair value of plan assets, end of year		0		0		0
Funded status of the plans		-44	[1]	-46	[1]
Amounts recognized in accumulated other comprehensive income:
Net actuarial (gain) loss		19		25
Prior service (credit) cost		-28		-45
Transition obligation		0		0
Total included in accumulated other comprehensive income		($9)		($20)
[1]	Recognized in other liabilities in the consolidated balance sheets

BENEFIT_PLANS_WeightedAverage_

BENEFIT PLANS - Weighted-Average Actuarial Assumptions (Detail)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Oct. 31, 2013
Japanese Pension Plan
Weighted-average actuarial assumptions:
Discount rate - net periodic benefit cost	2.25%		2.25%		2.25%
Discount rate - benefit obligations	1.75%		2.25%		2.25%
Expected long-term return on plan assets	2.00%		2.00%		2.50%
U.S. Pension Plan
Weighted-average actuarial assumptions:
Discount rate - net periodic benefit cost	4.75%		4.25%		4.75%
Discount rate - benefit obligations	4.50%		4.75%		4.25%
Expected long-term return on plan assets	7.50%		7.50%		7.50%
Rate of compensation increase	4.00%		4.00%		4.00%
Other Postretirement Benefit Plans, Defined Benefit
Weighted-average actuarial assumptions:
Discount rate - net periodic benefit cost	4.75%		4.25%		4.75%
Discount rate - benefit obligations	4.50%		4.75%		4.25%		4.75%
Health care cost trend rates	5.70%	[1]	6.40%	[1]	5.70%	[1]
Defined benefit plan, ultimate health care cost trend rate	4.60%		4.60%		4.70%
Defined benefit plan number of years that rate reaches ultimate trend rate	78 years		78 years		79 years
[1]	For the years 2014, 2013 and 2012, the health care cost trend rates are expected to trend down to 4.6% in 78 years, 4.6% in 78 years, and 4.7% in 79 years, respectively.

BENEFIT_PLANS_OnePercentage_Po

BENEFIT PLANS - One-Percentage Point Increase and Decrease in Assumed Health Care Cost Trend Rates (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Increase in total service and interest costs	$0
Increase in postretirement benefit obligation	3
Decrease in total service and interest costs	0
Decrease in postretirement benefit obligation	$2

BENEFIT_PLANS_Net_Periodic_Ben

BENEFIT PLANS - Net Periodic (Benefit) Cost Included in Acquisition and Operating Expenses (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Japanese Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$15	$16	$18
Interest cost	9	10	7
Expected return on plan assets	-4	-3	-4
Amortization of net actuarial loss	1	2	3
Amortization of prior service cost	0	0	0
Net periodic (benefit) cost	21	25	24
U.S. Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	20	22	18
Interest cost	38	23	24
Expected return on plan assets	-20	-17	-16
Amortization of net actuarial loss	11	15	11
Amortization of prior service cost	0	0	0
Net periodic (benefit) cost	49	43	37
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1	5	6
Interest cost	2	3	4
Expected return on plan assets	0	0	0
Amortization of net actuarial loss	3	2	1
Amortization of prior service cost	-17	-4	0
Net periodic (benefit) cost	($11)	$6	$11

BENEFIT_PLANS_Summary_of_Amoun

BENEFIT PLANS - Summary of Amounts Recognized in Other Comprehensive Loss (Income) (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	$12	($14)	($10)
Amortization of net actuarial loss	-1	-2	-3
Prior service cost (credit)	0	0	0
Amortization of prior service cost	0	0	0
Total	11	-16	-13
U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	67	-59	45
Amortization of net actuarial loss	-11	-15	-11
Prior service cost (credit)	0	-4	-1
Amortization of prior service cost	0	0	0
Total	56	-78	33
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	-3	-7	5
Amortization of net actuarial loss	-3	-2	-1
Prior service cost (credit)	0	-51	2
Amortization of prior service cost	17	4	0
Total	$11	($56)	$6

BENEFIT_PLANS_Expected_Benefit

BENEFIT PLANS - Expected Benefit Payments (Detail) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Japanese Pension Plan
Schedule of Postemployment Expected Future Benefit Payments [Line Items]
2015	$7
2016	11
2017	8
2018	7
2019	9
2020-2024	63
U.S. Pension Plan
Schedule of Postemployment Expected Future Benefit Payments [Line Items]
2015	20
2016	21
2017	28
2018	26
2019	27
2020-2024	159
Other Postretirement Benefit Plans, Defined Benefit
Schedule of Postemployment Expected Future Benefit Payments [Line Items]
2015	2
2016	2
2017	3
2018	3
2019	4
2020-2024	$22

BENEFIT_PLANS_Asset_Allocation

BENEFIT PLANS - Asset Allocation Targets (Detail)	12 Months Ended
	Dec. 31, 2014
Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	100.00%
U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	100.00%
Domestic equity securities | Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	0.00%
Domestic equity securities | U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	40.00%
International equity securities | Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	15.00%
International equity securities | U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	20.00%
Fixed income funds | Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	70.00%
Fixed income funds | U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	40.00%
Other Investments | Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	15.00%
Other Investments | U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Asset allocation targets	0.00%

BENEFIT_PLANS_Fair_Value_Hiera

BENEFIT PLANS - Fair Value Hierarchy Levels of Funded Pension Plans' Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Japanese Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$183	$182	$187
U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	341	313	261
U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	341	313
U S large cap equity securities | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	116	110
International equity securities | Japanese Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	34	34
Japanese bonds | Japanese Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	72	60
International bonds | Japanese Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	44	43
Mutual funds | Japanese Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0	21
Insurance contracts | Japanese Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	22	24
Fixed income funds | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	136	103
Aflac Incorporated Common Stock | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	4	4
Cash and cash equivalents | Japanese Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	11	0
U S mid cap equity securities | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	14	19
Real estate equity funds | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	10	9
International fund | U.S. Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$61	$68

COMMITMENTS_AND_CONTINGENT_LIA2

COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Detail)

12 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

agreements

IBM Mainframe Computer Operations and Support Agreement

IBM Mainframe Computer Operations and Support Agreement

IBM Distributed Computer Mid Range Server Operations and Support Agreement

IBM Distributed Computer Mid Range Server Operations and Support Agreement

IBM Application Maintenance and Development Services Agreement

IBM Application Maintenance and Development Services Agreement

Accenture Application Maintenance and Development Services Agreement

Accenture Application Maintenance and Development Services Agreement

NTTDATA Application Maintenance and Development Services

NTTDATA Application Maintenance and Development Services

NTT Comware Application Maintenance and Development Services

NTT Comware Application Maintenance and Development Services

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

USD ($)

JPY (¥)

Commitments and Contingencies Disclosure [Line Items]

Number of operating service agreements, technology and consulting

3

Number of operating service agreements, management consulting and technology

1

Outsourcing agreements, remaining term

1 year

1 year

1 year

1 year

3 years

3 years

3 years

3 years

2 years

2 years

3 years

3 years

Outsourcing agreements, aggregate remaining cost

$40

¥ 4,800

$32

¥ 3,900

$36

¥ 4,400

$31

¥ 3,800

$19

¥ 2,300

$19

¥ 2,300

Number of operating service agreements, information technology and data services

2

Operating Leases, lease terms

expire in various years through 2022

COMMITMENTS_AND_CONTINGENT_LIA3

COMMITMENTS AND CONTINGENT LIABILITIES - Future Minimum Lease Payments due under Non-Cancelable Operating Leases (Detail) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$55
2016	29
2017	19
2018	11
2019	7
Thereafter	8
Total future minimum lease payments	$129

Unaudited_Consolidated_Quarter1

Unaudited Consolidated Quarterly Financial Data (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Condensed Consolidating Statement of Operations [Line Items]
Net premium income	$4,489	$4,841	$4,888	$4,854	$4,910	$5,028	$5,013	$5,184	$19,072	$20,135	$22,148
Net investment income	808	841	843	827	826	821	813	833	3,319	3,293	3,473
Realized investment gains (losses)	143	16	102	-46	20	22	201	156
Other income	74	38	5	5	45	15	17	35	122	112	92
Total revenues	5,514	5,736	5,838	5,640	5,801	5,886	6,044	6,208	22,728	23,939	25,364
Total benefits and expenses	4,439	4,662	4,600	4,536	4,773	4,817	4,686	4,847	18,237	19,123	21,062
Earnings before income taxes	1,075	1,074	1,238	1,104	1,028	1,069	1,358	1,361	4,491	4,816	4,302
Total income tax expense	372	368	428	372	353	367	469	469	1,540	1,658	1,436
Net earnings	$703	$706	$810	$732	$675	$702	$889	$892
Net earnings per basic share	$1.57	$1.56	$1.79	$1.61	$1.46	$1.51	$1.91	$1.91	$6.54	$6.80	$6.14
Net earnings per diluted share	$1.57	$1.56	$1.78	$1.60	$1.45	$1.50	$1.90	$1.90	$6.50	$6.76	$6.11

SUBSEQUENT_EVENTS_Additional_I

SUBSEQUENT EVENTS Additional Information (Details) (Subsequent Event, USD $)	Feb. 25, 2015
In Millions, unless otherwise specified
Subsequent Event
Subsequent Event [Line Items]
Bank loan investment program allocation	$750
Bank loan investment program funded	700
High yield corporate bonds program allocation	500
High yield corporate bonds program funded	135
Middle market loan program allocation	300
Middle market loan program funded	$5

Schedule_II_Aflac_Incorporated

Schedule II - Aflac Incorporated (Parent Only) - Condensed Statement of Earnings (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Condensed Income Statements, [Line Items]
Net investment income	$808	$841	$843	$827	$826	$821	$813	$833	$3,319		$3,293		$3,473
Realized investment gains (losses)									215		399		-349
Total revenues	5,514	5,736	5,838	5,640	5,801	5,886	6,044	6,208	22,728		23,939		25,364
Interest expense									317		293		261
Other operating expenses									178		193		195
Earnings before income taxes	1,075	1,074	1,238	1,104	1,028	1,069	1,358	1,361	4,491		4,816		4,302
Current tax expense (benefit)									1,079		1,236		816
Deferred tax expense (benefit)									461		422		620
Total income tax expense	372	368	428	372	353	367	469	469	1,540		1,658		1,436
Net earnings									2,951		3,158		2,866
Parent Company
Condensed Income Statements, [Line Items]
Dividends from subsidiaries									1,483	[1]	962	[1]	0	[1]
Management and service fees from subsidiaries									272	[1]	292	[1]	249	[1]
Net investment income									13		11		20
Interest from subsidiaries									6	[1]	7	[1]	7	[1]
Realized investment gains (losses)									45		10		1
Change in fair value on the cross-currency interest rate swaps									314		274		154
Other income									-11		1		-7
Total revenues									2,122		1,557		424
Interest expense									243		208		184
Other operating expenses									88		79		72
Total operating expenses									331		287		256
Earnings before income taxes									1,791		1,270		168
Current tax expense (benefit)									1		0		1
Deferred tax expense (benefit)									120		98		50
Total income tax expense									121		98		51
Earnings before equity in undistributed earnings of subsidiaries									1,670		1,172		117
Equity in undistributed earnings of subsidiaries									1,281	[1]	1,986	[1]	2,749	[1]
Net earnings									$2,951		$3,158		$2,866
[1]	Eliminated in consolidation

Schedule_II_Aflac_Incorporated1

Schedule II - Aflac Incorporated (Parent Only) - Condensed Statements of Comprehensive Income (Loss) (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net earnings	$2,951		$3,158		$2,866
Foreign currency translation adjustments:
Unrealized foreign currency translation gains (losses) during period - parent only	-1,455		-1,588		-287
Unrealized gains (losses) on investment securities:
Unrealized holding gains (losses) on investment securities during period - parent only	5,947		-2,362		1,660
Pension liability adjustment during period	-76		157		-20
Total other comprehensive income (loss) before income taxes	4,345		-3,859		1,828
Income tax expense (benefit) related to items of other comprehensive income (loss)	1,803		-581		1,078
Other comprehensive income (loss), net of income taxes	2,542	[1]	-3,278	[1]	750
Total comprehensive income (loss)	5,493		-120		3,616
Parent Company
Condensed Financial Statements, Captions [Line Items]
Net earnings	2,951		3,158		2,866
Foreign currency translation adjustments:
Unrealized foreign currency translation gains (losses) during period - parent only	39		48		95
Equity in unrealized foreign currency translation gains (losses) of subsidiaries during period	-1,494		-1,636		-382
Unrealized gains (losses) on investment securities:
Unrealized holding gains (losses) on investment securities during period - parent only	9		-12		15
Equity in unrealized holding gains (losses) on investment securities held by subsidiaries during period	5,938		-2,350		1,645
Equity in reclassification adjustment for realized (gains) losses of subsidiaries included in net earnings	-54		-56		497
Unrealized gains (losses) on derivatives during period	-17		-10		-22
Pension liability adjustment during period	-76		157		-20
Total other comprehensive income (loss) before income taxes	4,345		-3,859		1,828
Income tax expense (benefit) related to items of other comprehensive income (loss)	1,803		-581		1,078
Other comprehensive income (loss), net of income taxes	2,542		-3,278		750
Total comprehensive income (loss)	$5,493		($120)		$3,616
[1]	All amounts in the table above are net of tax.

Schedule_II_Aflac_Incorporated2

Schedule II - Aflac Incorporated (Parent Only) - Condensed Balance Sheet (Detail) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Investments and cash:
Other investments	$171		$463
Cash and cash equivalents	4,658		2,543		2,041	2,249
Total investments and cash	107,341		108,459
Other assets	2,120	[1]	1,606	[1]
Total assets	119,767		121,307		131,094
Liabilities:
Income taxes	5,293		3,718
Notes payable	5,268		4,891
Other liabilities	4,719	[2]	2,850	[2]
Total liabilities	101,420		106,687
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2014 and 2013; issued 668,132 shares in 2014 and 667,046 shares in 2013	67		67
Additional paid-in capital	1,711		1,644
Retained earnings	22,156		19,885
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)	-2,541		-1,505
Unrealized gains (losses) on investment securities	4,672		1,035
Unrealized gains (losses) on derivatives	-26		-12
Pension liability adjustment	-126		-81
Treasury stock, at average cost	-7,566		-6,413
Total shareholders' equity	18,347		14,620		15,978
Total liabilities and shareholders' equity	119,767		121,307
Parent Company
Investments and cash:
Fixed maturity securities available for sale, at fair value (amortized cost $419 in 2014 and $322 in 2013)	437		332
Investments in subsidiaries	21,430	[3]	17,678	[3]
Other investments	24		313
Cash and cash equivalents	1,638		1,081		830	385
Total investments and cash	23,529		19,404
Due from subsidiaries	116	[3]	128	[3]
Other assets	766		464
Total assets	24,411		19,996
Liabilities:
Income taxes	6		-120
Employee benefit plans	282		246
Notes payable	5,285		4,910
Other liabilities	491		340
Total liabilities	6,064		5,376
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2014 and 2013; issued 668,132 shares in 2014 and 667,046 shares in 2013	67		67
Additional paid-in capital	1,711		1,644
Retained earnings	22,156		19,885
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)	-2,541		-1,505
Unrealized gains (losses) on investment securities	4,672		1,035
Unrealized gains (losses) on derivatives	-26		-12
Pension liability adjustment	-126		-81
Treasury stock, at average cost	-7,566		-6,413
Total shareholders' equity	18,347		14,620
Total liabilities and shareholders' equity	$24,411		$19,996
[1]	Includes $106 in 2014 and 2013 of derivatives from consolidated variable interest entities
[2]	Includes $318 in 2014 and $207 in 2013 of derivatives from consolidated variable interest entities
[3]	Eliminated in consolidation

Schedule_II_Aflac_Incorporated3

Schedule II - Aflac Incorporated (Parent Only) - Condensed Balance Sheet Parenthetical (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, except Share data in Thousands, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
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)	668,132	667,046	665,239	663,639
Parent Company
Condensed Financial Statements, Captions [Line Items]
Securities available for sale, fixed maturities, amortized cost	$419	$322
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)	668,132	667,064

Schedule_II_Aflac_Incorporated4

Schedule II - Aflac Incorporated (Parent Only) - Condensed Statements of Cash Flows (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Cash flows from operating activities:
Net earnings	$2,951		$3,158		$2,866
Adjustments to reconcile net earnings to net cash provided from operating activities:
Change in income tax liabilities	123		993		712
Other, net	309		401		-138
Net cash provided (used) by operating activities	6,550		10,547		14,952
Cash flows from investing activities:
Fixed maturity securities sold	4,178		9,631		7,385
Fixed maturity securities purchased	-10,978		-22,967		-19,533
Other investments sold (purchased)	272		-319		-6
Net cash provided (used) by investing activities	-4,241		-11,091		-16,952
Cash flows from financing activities:
Purchases of treasury stock	-1,210		-813		-118
Proceeds from borrowings	750		700		1,506
Principal payments under debt obligations	-335		0		-341
Dividends paid to shareholders	-654		-635		-603
Treasury stock reissued	33		88		32
Net change in amount due to/from subsidiaries	16		6		12
Net cash provided (used) by financing activities	-147		1,136		1,945
Net change in cash and cash equivalents	2,115		502		-208
Cash and cash equivalents, beginning of period	2,543		2,041		2,249
Cash and cash equivalents, end of period	4,658		2,543		2,041
Parent Company
Cash flows from operating activities:
Net earnings	2,951		3,158		2,866
Adjustments to reconcile net earnings to net cash provided from operating activities:
Equity in undistributed earnings of subsidiaries	-1,281	[1]	-1,986	[1]	-2,749	[1]
Change in income tax liabilities	115		155		111
Other, net	-72		11		-242
Net cash provided (used) by operating activities	1,713		1,338		-14
Cash flows from investing activities:
Fixed maturity securities sold	38		8		13
Fixed maturity securities purchased	-105		-206		-26
Other investments sold (purchased)	290		-298		-3
Net cash provided (used) by investing activities	223		-496		-16
Cash flows from financing activities:
Purchases of treasury stock	-1,210		-813		-118
Proceeds from borrowings	750		700		1,506
Principal payments under debt obligations	-335		0		-380
Dividends paid to shareholders	-654		-635		-603
Treasury stock reissued	33		88		70
Proceeds from exercise of stock options	23		41		21
Net change in amount due to/from subsidiaries	14	[1]	28	[1]	-21	[1]
Net cash provided (used) by financing activities	-1,379		-591		475
Net change in cash and cash equivalents	557		251		445
Cash and cash equivalents, beginning of period	1,081		830		385
Cash and cash equivalents, end of period	$1,638		$1,081		$830
[1]	Eliminated in consolidation

Schedule_II_Aflac_Incorporated5

Schedule II - Aflac Incorporated (Parent Only) - Summary of Notes Payable (Detail) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Notes payable	$5,268		$4,891
Parent Company
Condensed Financial Statements, Captions [Line Items]
Notes payable	5,285		4,910
Parent Company | 3.45% senior notes due August 2015
Condensed Financial Statements, Captions [Line Items]
Notes payable	300		300
Parent Company | 2.65% senior notes due February 2017
Condensed Financial Statements, Captions [Line Items]
Notes payable	653	[1]	655	[1]
Parent Company | 8.50% senior notes due May 2019
Condensed Financial Statements, Captions [Line Items]
Notes payable	850		850
Parent Company | 4.00% senior notes due February 2022
Condensed Financial Statements, Captions [Line Items]
Notes payable	350	[2]	349	[2]
Parent Company | 3.625% senior notes due June 2023
Condensed Financial Statements, Captions [Line Items]
Notes payable	700		700
Parent Company | 3.625% senior notes due November 2024
Condensed Financial Statements, Captions [Line Items]
Notes payable	749		0
Parent Company | 6.90% senior notes due December 2039
Condensed Financial Statements, Captions [Line Items]
Notes payable	397	[2]	396	[2]
Parent Company | 6.45% senior notes due August 2040
Condensed Financial Statements, Captions [Line Items]
Notes payable	448	[2]	448	[2]
Parent Company | 5.50% subordinated notes due September 2052
Condensed Financial Statements, Captions [Line Items]
Notes payable	500		500
Parent Company | 2.26% yen-denominated Uridashi notes due September 2016
Condensed Financial Statements, Captions [Line Items]
Notes payable	83		95
Parent Company | 1.47% yen-denominated Samurai notes paid July 2014
Condensed Financial Statements, Captions [Line Items]
Notes payable	0		272
Parent Company | 1.84% yen-denominated Samurai notes due July 2016
Condensed Financial Statements, Captions [Line Items]
Notes payable	131		150
Parent Company | Variable interest rate yen-denominated Samurai notes paid July 2014
Condensed Financial Statements, Captions [Line Items]
Notes payable	0		52
Parent Company | 3.60% yen-denominated loan due July 2015
Condensed Financial Statements, Captions [Line Items]
Notes payable	83		95
Parent Company | 3.00% yen-denominated loan due August 2015
Condensed Financial Statements, Captions [Line Items]
Notes payable	$41		$48
[1]	Principal amount plus an issuance premium that is being amortized over the life of the notes
[2]	Principal amount net of an issuance discount that is being amortized over the life of the notes

Schedule_II_Aflac_Incorporated6

Schedule II - Aflac Incorporated (Parent Only) - Summary of Notes Payable Parenthetical (Detail)

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2012

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

31-May-09

Dec. 31, 2014

Dec. 31, 2013

Feb. 29, 2012

Dec. 31, 2014

Dec. 31, 2013

Jun. 30, 2013

Dec. 31, 2014

Nov. 30, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2009

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Oct. 31, 2012

Sep. 30, 2012

Dec. 31, 2014

Dec. 31, 2013

Sep. 30, 2006

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Jul. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

3.45% senior notes due August 2015

3.45% senior notes due August 2015

3.45% senior notes due August 2015

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

2.65% senior notes due February 2017

8.50% senior notes due May 2019

8.50% senior notes due May 2019

8.50% senior notes due May 2019

4.00% senior notes due February 2022

4.00% senior notes due February 2022

4.00% senior notes due February 2022

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due November 2024

3.625% senior notes due November 2024

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.45% senior notes due August 2040

6.45% senior notes due August 2040

6.45% senior notes due August 2040

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

1.47% yen-denominated Samurai notes paid July 2014

1.47% yen-denominated Samurai notes paid July 2014

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

Variable interest rate yen-denominated Samurai notes paid July 2014

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

3.45% senior notes due August 2015

3.45% senior notes due August 2015

2.65% senior notes due February 2017

2.65% senior notes due February 2017

8.50% senior notes due May 2019

8.50% senior notes due May 2019

4.00% senior notes due February 2022

4.00% senior notes due February 2022

3.625% senior notes due June 2023

3.625% senior notes due June 2023

3.625% senior notes due November 2024

6.90% senior notes due December 2039

6.90% senior notes due December 2039

6.45% senior notes due August 2040

6.45% senior notes due August 2040

5.50% subordinated notes due September 2052

5.50% subordinated notes due September 2052

2.26% yen-denominated Uridashi notes due September 2016

2.26% yen-denominated Uridashi notes due September 2016

1.47% yen-denominated Samurai notes paid July 2014

1.84% yen-denominated Samurai notes due July 2016

1.84% yen-denominated Samurai notes due July 2016

Variable interest rate yen-denominated Samurai notes paid July 2014

3.60% yen-denominated loan due July 2015

3.60% yen-denominated loan due July 2015

3.00% yen-denominated loan due August 2015

3.00% yen-denominated loan due August 2015

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

JPY (¥)

Condensed Financial Statements, Captions [Line Items]

Notes payable, interest rate

3.45%

3.45%

2.65%

2.65%

2.65%

2.65%

8.50%

8.50%

4.00%

4.00%

4.00%

3.63%

3.63%

3.63%

3.63%

3.63%

6.90%

6.90%

6.45%

6.45%

5.50%

5.50%

5.50%

5.50%

2.26%

2.26%

1.47%

1.84%

1.84%

1.84%

1.30%

3.60%

3.60%

3.00%

3.00%

3.45%

3.45%

2.65%

2.65%

8.50%

8.50%

4.00%

4.00%

3.63%

3.63%

3.63%

6.90%

6.90%

6.45%

6.45%

5.50%

5.50%

2.26%

2.26%

1.47%

1.84%

1.84%

1.30%

3.60%

3.60%

3.00%

3.00%

Notes payable, principal amount

$300,000,000

$400,000,000

$250,000,000

$400,000,000

$850,000,000

$350,000,000

$350,000,000

$700,000,000

$700,000,000

$750,000,000

$750,000,000

$400,000,000

$450,000,000

$500,000,000

$50,000,000

$450,000,000

¥ 8,000,000,000

¥ 8,000,000,000

¥ 10,000,000,000

¥ 28,700,000,000

¥ 28,700,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 5,500,000,000

¥ 10,000,000,000

¥ 10,000,000,000

¥ 5,000,000,000

¥ 5,000,000,000

¥ 10,000,000,000

¥ 10,000,000,000

¥ 28,700,000,000

¥ 15,800,000,000

¥ 15,800,000,000

¥ 5,500,000,000

¥ 10,000,000,000

¥ 10,000,000,000

¥ 5,000,000,000

¥ 5,000,000,000

Schedule_II_Aflac_Incorporated7

Schedule II - Aflac Incorporated (Parent Only) - Additional Information (Detail) (Parent Company, Yen Denominated Uridashi and Samurai Notes, JPY ¥)	12 Months Ended
In Billions, unless otherwise specified	Dec. 31, 2009
Parent Company | Yen Denominated Uridashi and Samurai Notes
Condensed Financial Statements, Captions [Line Items]
Extinguishment of notes	¥ 2

Schedule_II_Aflac_Incorporated8

Schedule II - Aflac Incorporated - Aggregate Contractual Maturities of Notes Payable (Detail) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
2015	$428
2016	201
2017	653
2018	2
2019	851
Thereafter	3,150
Total	5,285
Parent Company
Condensed Financial Statements, Captions [Line Items]
2015	424
2016	214
2017	650
2018	0
2019	850
Thereafter	3,150
Total	$5,288

Schedule_II_Aflac_Incorporated9

Schedule II - Aflac Incorporated (Parent Only) - Supplemental Disclosure of Cash Flow Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Cash Flow, Supplemental [Line Items]
Interest paid	$241	$210	$178
Shareholder dividend reinvestment
Noncash financing activities:
Treasury stock issued for shareholder dividend reinvestment	26	25	24
Parent Company
Schedule of Cash Flow, Supplemental [Line Items]
Interest paid	241	205	181
Parent Company | Shareholder dividend reinvestment
Noncash financing activities:
Treasury stock issued for shareholder dividend reinvestment	$26	$25	$25

SCHEDULE_III_SUPPLEMENTARY_INS1

SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION - (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplementary Insurance Information, by Segment [Line Items]
Deferred policy acquisition costs	$8,273				$8,798				$8,273	$8,798
Future Policy Benefits & Unpaid Policy Claims	69,276				72,899				69,276	72,899
Unearned premiums	8,626				10,642				8,626	10,642
Other policyholders' funds	6,031				5,861				6,031	5,861
Net earned premiums	4,489	4,841	4,888	4,854	4,910	5,028	5,013	5,184	19,072	20,135	22,148
Net investment income	808	841	843	827	826	821	813	833	3,319	3,293	3,473
Benefits and claims, net									12,937	13,813	15,330
Amortization of deferred policy acquisition costs									1,108	1,074	1,117
Other Operating Expenses									4,192	4,236	4,615
Premiums Written									18,550	21,104	28,650
Aflac Japan
Supplementary Insurance Information, by Segment [Line Items]
Deferred policy acquisition costs	5,211				5,819				5,211	5,819	6,801
Future Policy Benefits & Unpaid Policy Claims	60,036				64,122				60,036	64,122
Unearned premiums	8,509				10,520				8,509	10,520
Other policyholders' funds	6,030				5,660				6,030	5,660
Net earned premiums									13,861	14,982	17,151
Net investment income									2,662	2,651	2,845
Benefits and claims, net									10,084	10,924	12,496
Amortization of deferred policy acquisition costs									649	641	716
Other Operating Expenses									2,364	2,495	2,937
Premiums Written									13,352	15,960	23,662
Aflac U.S.
Supplementary Insurance Information, by Segment [Line Items]
Deferred policy acquisition costs	3,062				2,979				3,062	2,979	2,857
Future Policy Benefits & Unpaid Policy Claims	9,239				8,775				9,239	8,775
Unearned premiums	117				122				117	122
Other policyholders' funds	0				201				0	201
Net earned premiums									5,211	5,153	4,996
Net investment income									645	632	613
Benefits and claims, net									2,853	2,889	2,834
Amortization of deferred policy acquisition costs									459	433	400
Other Operating Expenses									1,474	1,431	1,397
Premiums Written									5,198	5,144	4,988
All other
Supplementary Insurance Information, by Segment [Line Items]
Deferred policy acquisition costs	0				0				0	0
Future Policy Benefits & Unpaid Policy Claims	1				2				1	2
Unearned premiums	0				0				0	0
Other policyholders' funds	1				0				1	0
Net earned premiums									0	0	1
Net investment income									12	10	15
Benefits and claims, net									0	0	0
Amortization of deferred policy acquisition costs									0	0	1
Other Operating Expenses									354	310	281
Premiums Written									$0	$0	$0

SCHEDULE_IV_REINSURANCE_Schedu

SCHEDULE IV REINSURANCE Schedule IV - Reinsurance (Detail) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Gross Amount	$144,374				$157,022				$144,374	$157,022	$173,791
Ceded to Other Companies	3,298				3,245				3,298	3,245	3,867
Assumed from Other Companies	0				0				0	0	0
Net Amount	141,076				153,777				141,076	153,777	169,924
Percentage of Amount Assumed to Net	0.00%				0.00%				0.00%	0.00%	0.00%
Gross amount									19,412	20,233	22,167
Ceded to Other Companies									350	110	33
Assumed from Other companies									10	12	14
Net Amount	4,489	4,841	4,888	4,854	4,910	5,028	5,013	5,184	19,072	20,135	22,148
Percentage of Amount Assumed to Net									0.00%	0.00%	0.00%
Health insurance
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Gross amount									14,648	15,393	17,541
Ceded to Other Companies									339	98	19
Assumed from Other companies									10	12	14
Net Amount									14,319	15,307	17,536
Percentage of Amount Assumed to Net									0.00%	0.00%	0.00%
Life insurance
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Gross amount									4,764	4,840	4,626
Ceded to Other Companies									11	12	14
Assumed from Other companies									0	0	0
Net Amount									$4,753	$4,828	$4,612
Percentage of Amount Assumed to Net									0.00%	0.00%	0.00%