Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 17,001	$ 46,007	$ 30,069	$ 51,565
Other Comprehensive Income (Loss):
Foreign currency translation gains (losses)	(92)	(509)	(13)	135
Income tax benefit (expense)	0	28	(68)	25
Other comprehensive income (loss), net of tax	(92)	(481)	(81)	160
Comprehensive Income	16,909	45,526	29,988	51,725
Comprehensive Income attributable to Noncontrolling Interests in Subsidiaries	2,448	881	7,783	5,798
Comprehensive Income attributable to SEACOR Holdings Inc.	$ 14,461	$ 44,645	$ 22,205	$ 45,927