Consolidated Statements of Comprehensive Loss - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net loss including noncontrolling interest	$ (18.6)	$ (125.2)
Net pension adjustments, net of tax:
Liability adjustments for defined benefit pension plans	0.0	(2.7)
Reclassification of adjustments for defined benefit plans recorded in net loss	1.4	3.2
Total net pension adjustments	1.4	0.5
Net foreign currency translation:
Unrealized foreign currency translation losses	0.3	(0.8)
Realized cumulative translation adjustments from disposal of businesses	0.0	75.8
Total net foreign currency translation	0.3	75.0
Total other comprehensive income, net of tax	1.7	75.5
Comprehensive loss including noncontrolling interest	(16.9)	(49.7)
Less: Comprehensive loss attributable to noncontrolling interest	(10.3)	0.0
Comprehensive loss attributable to GlassBridge Enterprises, Inc.	$ (6.6)	$ (49.7)