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

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

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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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Value of stock issued pursuant to acquisitions during the period.

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Significant Transactions - PassportCard/DavidShield (Details) - USD ($) $ in Millions	May 07, 2020	Apr. 04, 2019	Jan. 24, 2018	Dec. 31, 2020	May 06, 2020	Dec. 31, 2019
Other Significant Noncash Transactions [Line Items]
Payments to acquire business, net		$ 81.4
DavidShield
Other Significant Noncash Transactions [Line Items]
Ownership interest (as a percent)			50.00%
PassportCard
Other Significant Noncash Transactions [Line Items]
Ownership interest (as a percent)			50.00%
DavidShield & PassportCard
Other Significant Noncash Transactions [Line Items]
Ownership interest (as a percent)	53.80%			53.80%	50.00%	50.00%
Payments to acquire businesses, gross			$ 41.8
Payments to acquire business, net			$ 28.3
Additional investment in acquisition	$ 15.0