Acquisition - Narrative (Details) - Cincinnati Global £ in Millions, $ in Millions	Feb. 28, 2019 USD ($)	Feb. 28, 2019 GBP (£)
Business Acquisition
Aggregate consideration paid	$ 63	£ 47
Broker Relationships And Internally Developed Technology \| Minimum
Business Acquisition
Useful life	5 years	5 years
Broker Relationships And Internally Developed Technology \| Maximum
Business Acquisition
Useful life	15 years	15 years
Previously Reported
Business Acquisition
Aggregate consideration paid	$ 64	£ 48
Adjustment to purchase price
Business Acquisition
Aggregate consideration paid		£ 1

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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.

+ References

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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

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