Condensed Consolidated Statement Of Changes In Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Shares Held In Treasury [Member]	Accumulated Other Comprehensive Loss [Member]	Non-Controlling Interests In Subsidiaries [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	$ 1,196,268	$ 379	$ 1,518,635	$ 910,723	$ (1,357,331)	$ (11,514)	$ 135,376
Employee Stock Purchase Plan	728	0	0	0	728	0	0
Exercise of stock options	7,271	1	7,270	0	0	0	0
Director stock awards	43	0	43	0	0	0	0
Restricted stock	0	2	2	0	0	0	0
Exercise of conversion option in convertible debt	3	0	3	0	0	0	0
Distribution of SEACOR Marine stock to shareholders	(527,691)	0	2,656	(521,859)	0	10,125	(18,613)
Purchase of conversion option in convertible debt, net of tax	(793)	0	793	0	0	0	0
Purchases of treasury shares	(7,569)	0	0	0	(7,569)	0	0
Amortization of share awards	21,137	0	21,137	0	0	0	0
cancellation of restricted stock	0	0	101	0	101	0	0
Purchase of subsidiary shares from noncontrolling interests	(3,693)	0	(1,114)	0	0	0	(2,579)
Consolidation of 50% or less owned companies	17,374	0	0	0	0	0	17,374
Distributions to noncontrolling interests	7,430	0	0	0	0	0	7,430
Comprehensive income:
Net income attributable to SEACOR Holdings Inc.	(28,725)	0	0		0	0
Net Income Attributable to Noncontrolling Interests in Subsidiaries	10,296
Net Loss	(18,429)
Other comprehensive income	1,005	0	0	0	0	844	161
Total equity	$ 678,224	$ 382	$ 1,547,936	$ 360,139	$ (1,364,273)	$ (545)	$ 134,585