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Subsequent Event - (Details) - Subsequent Event € / shares in Units, € in Millions, shares in Millions, $ in Millions	1 Months Ended	2 Months Ended
	Feb. 10, 2021 EUR (€) € / shares	Feb. 24, 2021 USD ($) shares	Feb. 18, 2021 USD ($)
Subsequent Event [Line Items]
Stock Repurchased During Period, Shares | shares		4.6
Stock Repurchased During Period, Value		$ 154.9
Remaining share repurchase authorization		$ 761.6
Coface
Subsequent Event [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	29.50%
Business acquisition, share price (per share) | € / shares	€ 9.95
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value | €	€ 453
Barbican
Subsequent Event [Line Items]
Net Reinsurance To Close Portfolio Transfer			$ 380.0

X

- Definition

Net Reinsurance To Close Portfolio Transfer

+ References

No definition available.

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- Definition

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

+ References

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-SubTopic 10
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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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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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