Net Income (Loss) Attributable to Shareholders of Crawford & Company per Common Share - Schedule of Antidilutive Shares Excluded from Computation of Diluted Earnings per Share (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Shares Underlying Stock Options Excluded
Antidilutive Securities Excluded from Computation of (Loss) Earnings Per Share
Shares excluded from diluted earnings per share (shares)	353	2,011	724	1,962
Performance Stock Grants Excluded because Performance Conditions Have Not Been Met
Antidilutive Securities Excluded from Computation of (Loss) Earnings Per Share
Shares excluded from diluted earnings per share (shares)	398	1,289	284	1,125