Restatement (Details) (USD $)	3 Months Ended		6 Months Ended			6 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Jun. 30, 2013 Scenario, Previously Reported [Member]	Jun. 30, 2013 Era Group [Member]	Jun. 30, 2012 Era Group [Member]	Jun. 30, 2013 Era Group [Member]	Jun. 30, 2012 Era Group [Member]	Dec. 31, 2013 Era Group [Member]
Liability for Uncertain Tax Positions, Current							$ 10,100,000		$ 10,100,000		$ 10,100,000
Other current liabilities	122,424,000		122,424,000		93,093,000	112,310,000
Total current liabilities	220,728,000		220,728,000		265,641,000	210,614,000
Total liabilities	1,431,897,000		1,431,897,000		1,958,119,000	1,421,783,000
Retained earnings	1,056,583,000		1,056,583,000		1,473,509,000	1,066,697,000
Stockholders' equity attributable to parent, total	1,311,558,000		1,311,558,000		1,713,654,000	1,321,672,000
Total equity	1,336,436,000		1,336,436,000		1,742,675,000	1,346,550,000
Income (Loss) from Discontinued Operations, Net of Tax	0	4,804,000	(10,325,000)	19,989,000		(211,000)
Net Income	19,296,000	11,299,000	(2,065,000)	47,672,000		8,049,000	0	3,973,000	(9,233,000)	(334,000)
Net Income attributable to SEACOR Holdings Inc.	19,271,000	11,249,000	(1,717,000)	47,737,000		8,397,000
Income (Loss) from Continuing Operations Attributable to Parent	19,271,000	6,445,000	8,508,000	27,748,000		8,508,000
Discontinued operations, net of tax	0	4,804,000	(10,225,000)	19,989,000		(111,000)
Continuing operations	$ 0.97	$ 0.31	$ 0.43	$ 1.35		$ 0.43
Discontinued operations	$ 0.00	$ 0.24	$ (0.52)	$ 0.97		$ (0.01)
Earnings Per Share, Basic	$ 0.97	$ 0.55	$ (0.09)	$ 2.32		$ 0.42
Continuing operations	$ 0.91	$ 0.31	$ 0.42	$ 1.33		$ 0.42
Discontinued operations	$ 0.00	$ 0.23	$ (0.51)	$ 0.96		$ 0.00
Earnings Per Share, Diluted	$ 0.91	$ 0.54	$ (0.09)	$ 2.29		$ 0.42
Comprehensive Income	19,397,000	10,743,000	(4,719,000)	49,956,000		5,395,000
Comprehensive Income attributable to SEACOR Holdings Inc.	$ 19,349,000	$ 10,787,000	$ (3,919,000)	$ 49,864,000		$ 6,195,000