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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Significant Transactions - PassportCard/DavidShield (Details) - USD ($) $ in Millions	May 07, 2020	Jan. 24, 2018	Sep. 30, 2022	Dec. 31, 2021	May 06, 2020
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%
PassportCard/DavidShield
Other Significant Noncash Transactions [Line Items]
Ownership interest (as a percent)	53.80%		53.80%	53.80%	50.00%
Payments to acquire businesses, gross		$ 41.8
Payments to acquire business, net		$ 28.3
Stock issued during period, value, acquisitions	$ 15.0
Maximum loss exposure			$ 143.0