Business Acquisition, Effective Timeline of Acquisition

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- Definition

Business Combination, Consideration Transferred Percent

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Business Combination, Recognized Invested Assets

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
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-Topic 805
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- Definition

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

+ References

Reference 1: 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)
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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- Definition

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

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Billions															12 Months Ended
	Feb. 08, 2018	Jan. 21, 2018	Dec. 22, 2017	Sep. 29, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 22, 2016	Sep. 29, 2016	Jun. 27, 2016	Mar. 28, 2016	Dec. 21, 2015	Sep. 28, 2015	Jun. 25, 2015	Mar. 26, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	May 03, 2017
Subsequent Event [Line Items]
Dividends declared per common share															$ 1.28	$ 1.28	$ 0.81
Authorized amount of common Stock share repurchase																		$ 2.5
Aggregate remaining authorization amount of common Stock share repurchase															$ 2.3
Date of Shareholders of Record			Dec. 08, 2017	Sep. 15, 2017	Jun. 14, 2017	Mar. 15, 2017	Dec. 08, 2016	Sep. 15, 2016	Jun. 13, 2016	Mar. 14, 2016	Dec. 07, 2015	Sep. 14, 2015	Jun. 11, 2015	Mar. 12, 2015
Subsequent event
Subsequent Event [Line Items]
Dividends declared per common share	$ 0.32
Date Dividends Declared															Feb. 08, 2018
Date Dividends To Be Paid															Mar. 29, 2018
Date of Shareholders of Record															Mar. 15, 2018
Subsequent event \| Validus Holdings, Ltd
Subsequent Event [Line Items]
Payments to Acquire Business		$ 5.6
Transaction is expected to close		mid-2018
Subsequent event \| DSA Reinsurance Company, Ltd.
Subsequent Event [Line Items]
AIG Ownership Percent	100.00%
Subsequent event \| DSA Reinsurance Company, Ltd. \| Life and Retirement Companies
Subsequent Event [Line Items]
Transfer of reserves from various segment run off lines	$ 32.0
Subsequent event \| DSA Reinsurance Company, Ltd. \| General Insurance Companies
Subsequent Event [Line Items]
Transfer of reserves from various segment run off lines	5.0
Subsequent event \| DSA Reinsurance Company, Ltd. \| Legacy reporting segment
Subsequent Event [Line Items]
Percent of Insurance reserves in the Legacy reporting segment transferred															80.00%
Subsequent event \| DSA Reinsurance Company, Ltd. \| AIG Asset Management
Subsequent Event [Line Items]
Invested Assets the Licensed reinsurer will have	$ 40.0