Net Income Attributable to Shareholders of Crawford & Company per Common Share (Weighted Average Shares Issued) (Details) - Class A Non-Voting - shares shares in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
CRD-A issued under Non-Employee Director Stock Plan
Share-based Compensation Arrangement
Stock issued during period (shares)	81	76
CRD-A issued under the U.K. ShareSave Scheme
Share-based Compensation Arrangement
Stock issued during period (shares)	1	9
CRD-A issued under Executive Stock Bonus Plan
Share-based Compensation Arrangement
Stock issued during period (shares)	0	30

Number of new stock issued during the period.

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