Income (loss) Per Common Share - Computation of Weighted Average Basic and Diluted Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Numerator: Loss from continuing operations	$ (13,200)	$ (900)
Numerator: Less: loss attributable to noncontrolling interest	(400)
Numerator: Net loss from continuing operations attributable to GlassBridge Enterprises, Inc.	(13,200)	(900)
Numerator: Income from discontinued operations, net of income taxes		10,500
Net income (loss) attributable to GlassBridge Enterprises, Inc.	$ (12,800)	$ 9,600
Denominator: Weighted average number of common shares outstanding during the period - basic and diluted	25,200	25,700
Income (loss) per common share attributable to GlassBridge common shareholders - basic and diluted: Continuing operations	$ (507.69)	$ (36.98)
Income (loss) per common share attributable to GlassBridge common shareholders - basic and diluted: Discontinued operations		408.72
Net income (loss)	$ (507.69)	$ 371.74
Anti-dilutive shares excluded from calculation	0.0	0.0