The maximum useful life of a major finite-lived intangible asset class acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination).

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The minimum useful life of a major finite-lived intangible asset class acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination).

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The aggregate amount assigned of intangible assets acquired either individually or as part of a group of assets (in either an asset or business combination).

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The cash outflow associated with the acquisition of a business subsequent to period end, net of the cash acquired from the purchase.

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Percent of additional outstanding Winterthur shares tendered under the initial public tender offer.

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Percent of outstanding Winterthur shares acquired through open market purchases by February 11, 2011

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Cash and marketable securities acquired that was held by the acquired business.

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The term of an embedded derivative, expressed in years.

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The annual rate at which interest is recorded related to the five-year financing liability.

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Number of trading days public tender offer period was extended.

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The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 44
-Subparagraph a(1)

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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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The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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The aggregate cost of a major indefinite-lived intangible asset class acquired, during the period, either individually or as part of a group of assets (in either an asset acquisition or business combination).

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Percentage of voting equity interests acquired in the business combination.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
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The amount of acquisition cost of a business combination allocated to notes payables and long-term debt assumed from the acquired entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 37
-Subparagraph g

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 98-1

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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The total amount of [all] liabilities that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The net cash inflow or (outflow) associated with the aggregate amount of adjustment to the purchase price of a previous acquisition.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 15, 16

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Acquisitions and Divestitures (Detail 2) In Millions, unless otherwise specified	12 Months Ended				12 Months Ended		1 Months Ended
	Dec. 31, 2010 USD ($) years number	Dec. 31, 2009 USD ($) years number	Dec. 31, 2008 USD ($) years number	Dec. 31, 2010 JPY (¥)	Dec. 31, 2008 Patents USD ($) years	Dec. 31, 2008 Customer relationships and tradenames USD ($) years	Oct. 31, 2010 Cogent Inc. USD ($)	Apr. 30, 2010 A-One JPY (¥) years	Jun. 30, 2008 High Jump Software USD ($)	Dec. 31, 2010 Winterthur USD ($) number
Acquired intangible asset activity through business combinations
Acquired indefinite-lived intangible assets		$ 8	$ 58
Acquired finite-lived intangible assets	663	20	794		40	696
Acquired intangible assets		28
Acquired intangible assets, weighted-average life	11	8	13		11	13
Life, bottom of range (in years)	2	3	1
Life, top of range (in years)	17	12	19
Debt assumed	105	18	809
Acquisitions:
Embedded mirroring put and call options with respect to remaining minority shares, term (in years)								5
Proposed transaction aggregate value relative to all outstanding shares on fully diluted basis										450
Purchase price paid to acquire remaining noncontrolling interest							248
Acquired cash and marketable securities							532
Percent of outstanding shares of acquiree that tender offer was initially conditional upon, which was waived										67.00%
Percent of outstanding Winterthur shares acquired through open market purchases by February 11, 2011										15.00%
Percent of additional outstanding Winterthur shares tendered under the initial public tender offer										23.00%
Number of trading days public tender offer period was extended for										10
Five-year financed liability of 1.7 billion in Japanese Yen (approximately $18 million in USD)	18			1,700				1,700
Interest rate related to five-year financed liability								1.00%
Purchase price paid for business combinations (net of cash acquired) and certain acquisition costs and contingent consideration paid for previous business combinations during the period	1,830	69	1,394
Divestitures:
Proceeds from sale of businesses		5	88						85
Pre-tax loss on sale of business			$ (23)						$ (23)