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

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- Definition

Expiration date for the authorization to repurchase up to $1 billion.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Treasury Stock, Decrease In Capital In Excess Of Par Value

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(e))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph e

-Article 4

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.23(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 24

-Subparagraph c

-Article 7

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

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Stockholders' Equity - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	12 Months Ended			1 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2013	Nov. 10, 2014	Sep. 30, 2014	Feb. 18, 2015	Nov. 07, 2014
Equity, Class of Treasury Stock [Line Items]
Cash dividend declared	$ 1.11	$ 1.07	$ 1.03
Total Amount	$ 170,000,000us-gaap_Dividends	$ 167,000,000us-gaap_Dividends	$ 165,000,000us-gaap_Dividends
Value of shares repurchased	872,000,000	531,000,000	518,000,000
Common shares acquired in connection with employee stock plans, shares	0.4	0.3	0.7
Common shares acquired in connection with employee stock plans, amount	42,000,000	29,000,000	58,000,000
Aggregate statutory capital and surplus in our state regulated insurance subsidiaries	6,000,000,000	5,500,000,000
Aggregate minimum regulatory requirements of statutory capital and surplus	4,100,000,000	3,500,000,000
Dividends that may be paid to the parent company without prior approval by state regulatory authorities in 2014	800,000,000
Dividends that were paid to the parent company without prior approval by state regulatory authorities	927,000,000
Dividend Declared
Equity, Class of Treasury Stock [Line Items]
Cash dividend declared				$ 0.28
Dividend payable date				Jan. 30, 2015
Record Date				Dec. 31, 2014
Total Amount				42,000,000
Prior Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization						1,000,000,000
Shares repurchased in open market	1.60	5.77	6.25
Value of shares repurchased	195,000,000	502,000,000	460,000,000
Shares repurchased in open market, average price	$ 121.68	$ 86.97	$ 73.66
Remaining authorized amount						816,000,000
Current Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization						2,000,000,000
Expiration date of current authorization	Dec. 31, 2016
Shares repurchased in open market	4.10
Value of shares repurchased	535,000,000
Shares repurchased in open market, average price	$ 130.42
Current Authorization \| Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Remaining authorized amount							1,370,000,000
Accelerated Share Repurchase Agreement
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization								500,000,000
Shares repurchased in open market					3.06
Value of shares repurchased					400,000,000
Decrease in capital in excess of par value					$ 100,000,000