Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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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 net cash outflow or inflow associated with the acquisition or sale of a business segment during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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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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- Definition

Business Combination, Transaction Book Value Multiple

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Subsequent Event (Details) $ / shares in Units, $ in Billions		3 Months Ended
	May 02, 2017 $ / shares	Dec. 31, 2017 USD ($)	Mar. 31, 2017
Scenario, Forecast
Subsequent Event [Line Items]
Proceeds from acquisition \| $		$ 1.3
Intact Financial Corporation \| OneBeacon [Member] \| Subsequent Event
Subsequent Event [Line Items]
Acquisition price per share (in USD per share) \| $ / shares	$ 18.10
Transaction book value multiple	1.65
OneBeacon [Member]
Subsequent Event [Line Items]
Percentage of voting interest acquired			96.90%
Ownership interest (as a percent)			75.70%