Amount of dividends paid to our parent company without prior approval by state regulatory authorities

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Number of shares of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

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Cost of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

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Treasury Stock, Decrease In Capital In Excess Of Par Value

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Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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STOCKHOLDERS' EQUITY - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands								1 Months Ended	3 Months Ended	4 Months Ended	6 Months Ended	12 Months Ended
	Nov. 29, 2018	Nov. 28, 2018	Nov. 02, 2018	Mar. 26, 2018	Dec. 22, 2017	Aug. 28, 2017	Feb. 22, 2017	Feb. 28, 2019	Mar. 26, 2018	Dec. 31, 2017	Aug. 28, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 21, 2019	Dec. 21, 2017	Dec. 14, 2017	Feb. 16, 2017	Feb. 14, 2017
Equity, Class of Treasury Stock [Line Items]
Cash dividend declared (in USD per share)			$ 0.5
Total amount												$ 262,000,000	$ 216,000,000	$ 172,000,000
Share repurchase authorization																	$ 3,000,000,000.0		$ 2,250,000,000.00
Value of shares repurchased												$ 1,090,000,000	$ 3,365,000,000	$ 104,000,000
Common shares acquired in connection with employee stock plans (in shares)												400	500	600
Common shares acquired in connection with employee stock plans, amount												$ 116,000,000	$ 115,000,000	$ 104,000,000
Aggregate statutory capital and surplus in our state regulated insurance subsidiaries										$ 8,000,000,000		7,600,000,000	8,000,000,000
Aggregate minimum regulatory requirements of statutory capital and surplus										$ 4,800,000,000		5,200,000,000	4,800,000,000
Dividends that may be paid to the parent company without prior approval by state regulatory authorities in 2014												1,000,000,000
Dividends that were paid to the parent company without prior approval by state regulatory authorities												2,300,000,000	$ 1,400,000,000	$ 800,000,000
Dividend Declared
Equity, Class of Treasury Stock [Line Items]
Total amount												68,000,000
February 2017 ASR
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization																		$ 1,500,000,000.0
Share repurchase payment							$ 1,500,000,000
Shares repurchased in open market (in shares)						840	5,830			3,040	6,670
Value of shares repurchased						$ 300,000,000	$ 1,200,000,000			$ 750,000,000
Decrease in capital in excess of par value							$ 300,000,000
Average cost per share (in USD per share)											$ 224.81
December 2017 ASR
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization		$ 3,000,000,000.0														$ 1,000,000,000.0
Share repurchase payment					$ 1,000,000,000
Shares repurchased in open market (in shares)				460	3,280				3,740
Value of shares repurchased				$ 200,000,000	$ 800,000,000
Decrease in capital in excess of par value		150,000,000			$ 200,000,000
Average cost per share (in USD per share)									$ 267.55
November 2018 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization		$ 750,000,000
Share repurchase payment	$ 750,000,000
Shares repurchased in open market (in shares)	1,940
Value of shares repurchased	$ 600,000,000
Decrease in capital in excess of par value	$ 150,000,000
February 2017 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization												$ 2,250,000,000
Shares repurchased in open market (in shares)												0	9,710	0
Value of shares repurchased												$ 0	$ 2,250,000,000	$ 0
December 2017 Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization												$ 3,000,000,000
Shares repurchased in open market (in shares)												3,070	3,280	0
Value of shares repurchased												$ 1,024,000,000	$ 800,000,000	$ 0
Excluding Employee Stock Plans and ASR
Equity, Class of Treasury Stock [Line Items]
Shares repurchased in open market (in shares)												3,070	12,990	0
Value of shares repurchased												$ 1,024,000,000	$ 3,050,000,000	$ 0
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Remaining authorized amount															$ 1,176,000,000
Subsequent Event \| Dividend Declared
Equity, Class of Treasury Stock [Line Items]
Cash dividend declared (in USD per share)								$ 0.55