Consolidated Statements of Equity - USD ($) $ in Millions	Total	SPX Corporation Shareholders’ Equity	Common Stock	Paid-In Capital	Retained Earnings (Deficit)	Accum. Other Comprehensive Income	Common Stock In Treasury	Noncontrolling Interests
Balance at Dec. 31, 2014	$ 1,811.9	$ 1,808.7	$ 1.0	$ 2,608.0	$ 2,628.6	$ 62.6	$ (3,491.5)	$ 3.2
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(117.0)	(82.7)			(82.7)			(34.3)
Other comprehensive income, net	(133.9)	(133.9)				(133.9)
Dividends declared ($0.75 per share)	(30.9)	(30.9)			(30.9)
Incentive plan activity	14.7	14.7		14.7
Long-term incentive compensation expense	39.9	39.9		39.9
Restricted stock and restricted stock unit vesting, including related tax benefit of $0.6 and net of tax withholdings	(7.8)	(7.8)		(13.0)			5.2
Other changes in noncontrolling interests	5.3							5.3
Spin-Off of FLOW Business	(1,273.9)	(1,262.6)			(1,617.2)	354.6		(11.3)
Balance at Dec. 31, 2015	308.3	345.4	1.0	2,649.6	897.8	283.3	(3,486.3)	(37.1)
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(67.6)	(67.2)			(67.2)			(0.4)
Other comprehensive income, net	(48.2)	(48.2)				(48.2)
Incentive plan activity	8.8	8.8		8.8
Long-term incentive compensation expense	12.7	12.7		12.7
Restricted stock and restricted stock unit vesting, including related tax benefit of $0.6 and net of tax withholdings	(3.9)	(3.9)		(21.8)			17.9
Treasury share retirement	0.0		(0.5)	(1,285.4)	(1,662.2)		2,948.1
Adjustment related to redeemable noncontrolling interest (Note 13)	(17.3)	(56.0)		(56.0)				38.7
Other changes in noncontrolling interests	(1.2)							(1.2)
Balance at Dec. 31, 2016	191.6	191.6	0.5	1,307.9	(831.6)	235.1	(520.3)	0.0
Increase (Decrease) in Stockholders' Equity
Net income (loss)	89.3	89.3			89.3
Other comprehensive income, net	15.0	15.0				15.0
Incentive plan activity	11.3	11.3		11.3
Long-term incentive compensation expense	12.0	12.0		12.0
Restricted stock and restricted stock unit vesting, including related tax benefit of $0.6 and net of tax withholdings	(4.5)	(4.5)		(21.4)			16.9
Balance at Dec. 31, 2017	$ 314.7	$ 314.7	$ 0.5	$ 1,309.8	$ (742.3)	$ 250.1	$ (503.4)	$ 0.0