Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	$ 175,446	$ 186,964	$ 159,264
Unrealized net gains (losses) arising during the year	1,036	(18,014)	666
Net current period other comprehensive income (loss)	8,858	(20,768)	14,490
Ending Balance	162,567	175,446	186,964
AOCL attributable to shareholders of Crawford & Company
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(216,447)	(196,477)	(211,773)
Other comprehensive income (loss) before reclassifications	502	(10,032)
Unrealized net gains (losses) arising during the year	1,036	(18,014)
Amounts reclassified from accumulated other comprehensive income, total	8,002	8,076
Net current period other comprehensive income (loss)	9,540	(19,970)	15,296
Ending Balance	(206,907)	(216,447)	(196,477)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Adjustment for long-term intercompany transactions, net of tax	(928)	(1,838)	(836)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(36,352)	(26,320)
Other comprehensive income (loss) before reclassifications	502	(10,032)
Unrealized net gains (losses) arising during the year	0	0
Amounts reclassified from accumulated other comprehensive income, total	0	0
Net current period other comprehensive income (loss)	502	(10,032)
Ending Balance	(35,850)	(36,352)	(26,320)
Retirement liabilities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(180,095)	(170,157)
Other comprehensive income (loss) before reclassifications	0	0
Unrealized net gains (losses) arising during the year		(18,014)
Amounts reclassified from accumulated other comprehensive income, total	8,002	8,076
Net current period other comprehensive income (loss)	9,038	(9,938)
Ending Balance	$ (171,057)	$ (180,095)	$ (170,157)

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