Condensed Consolidated Statement Of Changes In Equity (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	$ 1,533,430	$ 1,533,430	$ 1,425,428
Employee Stock Purchase Plan		2,165
Exercise of stock options		5,035
Director stock awards		(153)
Restricted stock		223
Purchases of treasury shares		(127,151)
Amortization of share awards		11,683
Cancellation of restricted stock		0
Purchase of subsidiary shares from noncontrolling interests		(3,110)
Issuance of noncontrolling interest, net of issue costs		145,924
Dividends paid to noncontrolling interests		1,056
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.	27,463	60,039
Net Income (Loss) Attributable to Noncontrolling Interest	6,315	14,979
Net income	33,778	75,018
Other comprehensive income	(2,538)	(882)
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	375	375	372
Employee Stock Purchase Plan		0
Exercise of stock options		1
Director stock awards		0
Restricted stock		2
Purchases of treasury shares		0
Amortization of share awards		0
Cancellation of restricted stock		0
Purchase of subsidiary shares from noncontrolling interests		0
Issuance of noncontrolling interest, net of issue costs		0
Dividends paid to noncontrolling interests		0
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.		0
Other comprehensive income		0
Additional Paid-In Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	1,485,342	1,485,342	1,394,621
Employee Stock Purchase Plan		0
Exercise of stock options		5,034
Director stock awards		(153)
Restricted stock		200
Purchases of treasury shares		0
Amortization of share awards		(11,683)
Cancellation of restricted stock		(83)
Purchase of subsidiary shares from noncontrolling interests		(1,242)
Issuance of noncontrolling interest, net of issue costs		74,810
Dividends paid to noncontrolling interests		0
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.		0
Other comprehensive income		0
Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	1,155,309	1,155,309	1,095,270
Employee Stock Purchase Plan		0
Exercise of stock options		0
Director stock awards		0
Restricted stock		0
Purchases of treasury shares		0
Amortization of share awards		0
Cancellation of restricted stock		0
Purchase of subsidiary shares from noncontrolling interests		0
Issuance of noncontrolling interest, net of issue costs		0
Dividends paid to noncontrolling interests		0
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.		(60,039)
Other comprehensive income		0
Shares Held In Treasury [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	(1,213,267)	(1,213,267)	(1,088,219)
Employee Stock Purchase Plan		2,165
Exercise of stock options		0
Director stock awards		0
Restricted stock		21
Purchases of treasury shares		(127,151)
Amortization of share awards		0
Cancellation of restricted stock		83
Purchase of subsidiary shares from noncontrolling interests		0
Issuance of noncontrolling interest, net of issue costs		0
Dividends paid to noncontrolling interests		0
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.		0
Other comprehensive income		0
Accumulated Other Comprehensive Income (Loss) [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	(1,891)	(1,891)	(1,192)
Employee Stock Purchase Plan		0
Exercise of stock options		0
Director stock awards		0
Restricted stock		0
Purchases of treasury shares		0
Amortization of share awards		0
Cancellation of restricted stock		0
Purchase of subsidiary shares from noncontrolling interests		0
Issuance of noncontrolling interest, net of issue costs		0
Dividends paid to noncontrolling interests		0
Comprehensive income:
Net Income attributable to SEACOR Holdings Inc.		0
Other comprehensive income		699
Non-Controlling Interests In Subsidiaries [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total equity	107,562	107,562	24,576
Employee Stock Purchase Plan		0
Exercise of stock options		0
Director stock awards		0
Restricted stock		0
Purchases of treasury shares		0
Amortization of share awards		0
Cancellation of restricted stock		0
Purchase of subsidiary shares from noncontrolling interests		(1,868)
Issuance of noncontrolling interest, net of issue costs		71,114
Dividends paid to noncontrolling interests		1,056
Comprehensive income:
Net Income (Loss) Attributable to Noncontrolling Interest		(14,979)
Other comprehensive income		$ 183