Net Income (Loss) Per Share - Reconciliation of the numerator and denominator of the basic and diluted net (loss) income per share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerators:
Net income (loss)	$ (14,263)	$ 75	$ (32,339)	$ 9,699
Non-controlling interest	(211)	(238)	79	99
Net income (loss) attributable to Steel Excel Inc.	$ (14,474)	$ (163)	$ (32,260)	$ 9,798
Denominators:
Basic weighted average common shares outstanding (in Shares)	11,421	11,437	11,489	11,769
Effect of dilutive securities:
Stock-based awards (in shares)	0	0	0	21
Diluted weighted average common shares outstanding (in Shares)	11,421	11,437	11,489	11,790
Basic income (loss) per share attributable to Steel Excel Inc.:
Net income (loss) (in dollars per share)	$ (1.27)	$ (0.01)	$ (2.81)	$ 0.83
Diluted income (loss) per share attributable to Steel Excel Inc.:
Net income (loss) (in dollars per share)	$ (1.27)	$ (0.01)	$ (2.81)	$ 0.83
Antidilutive securities excluded (in shares)	15	23	15