Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 425.4	$ 99.0	$ 65.3
Other comprehensive income (loss), net:
Pension and postretirement liability adjustment, net of tax benefit of $1.2, $1.2, and $0.5 in 2021, 2020 and 2019, respectively		(3.6)	(1.8)
Net unrealized gains (losses) on qualifying cash flow hedges, net of tax (provision) benefit of $(1.5), $0.9, and $0.3 in 2021, 2020 and 2019, respectively		(2.8)	(1.0)
Foreign currency translation adjustments	14.1	10.6	2.2
Other comprehensive income (loss), net	15.4	4.2	(0.6)
Total comprehensive income	440.8	103.2	64.7
Less: Total comprehensive loss attributable to noncontrolling interests	0.0	0.0	0.0
Total comprehensive income attributable to SPX Corporation common stockholders	$ 440.8	$ 103.2	$ 64.7