Acquisitions, Discontinued Operations and Formation of Shanghai Electric JV (Details) In Millions, except Per Share data, unless otherwise specified	12 Months Ended				0 Months Ended	12 Months Ended				12 Months Ended						12 Months Ended			1 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended	0 Months Ended	12 Months Ended	1 Months Ended
	Dec. 31, 2012 USD ($) Y	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Feb. 28, 2011 B.W. Murdoch Ltd. ("Murdoch") USD ($)	Dec. 22, 2011 Clyde Union GBP (£)	Dec. 31, 2011 Clyde Union USD ($)	Dec. 31, 2010 Clyde Union USD ($)	Dec. 31, 2012 Clyde Union USD ($)	Dec. 22, 2011 Clyde Union USD ($)	Dec. 31, 2012 Clyde Union Customer lists USD ($) Y	Dec. 31, 2012 Clyde Union Customer relationships USD ($) Y	Dec. 31, 2012 Clyde Union Technology USD ($) Y	Dec. 31, 2012 Clyde Union Trademarks USD ($)	Dec. 22, 2011 Clyde Union Minimum GBP (£)	Dec. 22, 2011 Clyde Union Maximum GBP (£)	Jun. 30, 2010 Anhydro business ("Anhydro") USD ($)	Mar. 31, 2010 Torque Tension Systems Ltd. ("TTS") USD ($)	Jan. 31, 2010 Gerstenberg Schroder A/S ("Gerstenberg") USD ($)	Mar. 31, 2011 Flow Technology reportable segment B.W. Murdoch Ltd. ("Murdoch") USD ($)	Dec. 31, 2012 Flow Technology reportable segment Clyde Union GBP (£)	Dec. 22, 2011 Flow Technology reportable segment Clyde Union GBP (£)	Oct. 31, 2011 Flow Technology reportable segment e&e Verfahrenstechnik GmbH (e&e) EUR (€)	Oct. 31, 2011 Flow Technology reportable segment e&e Verfahrenstechnik GmbH (e&e) EUR (€)	Mar. 21, 2012 Flow Technology reportable segment Seital USD ($)	Mar. 31, 2012 Flow Technology reportable segment Seital USD ($)	Jul. 31, 2010 Flow Technology reportable segment Anhydro business ("Anhydro") USD ($)	Feb. 28, 2010 Flow Technology reportable segment Gerstenberg Schroder A/S ("Gerstenberg") USD ($)	Apr. 30, 2010 Industrial Products and Services Torque Tension Systems Ltd. ("TTS") USD ($)
Acquisitions
Maximum measurement period from the date of acquisition (in years)	1
Initial payment																					£ 500.0
Debt assumed and other adjustments																					11.0
Potential earn-out payment equal to number of times of Group EBITDA																				10
Deduction from Group EBITDA x 10																				475.0
Cash acquired in business acquisition									44.3													3.8	3.8	2.5		10.9	3.5	2.4
Debt assumed in business acquisition																								0.8			3.9
Revenues of the acquired business for the prior twelve months				13.0												71.0	9.0	57.0					15.3		14.0
Purchase price of the business acquired	34.3	747.5	114.8																8.1			11.7		28.8		59.1	30.9	15.7
Earn-out payment														0	250.0							3.5	3.5
Contribution by the sellers of acquired entity to the acquired business at the time of sale					25.0
Amount of increase in goodwill	73.6	3.8
Assets acquired:
Current assets, including cash and equivalents of $44.3								354.1
Property, plant and equipment								89.8
Goodwill								377.2
Intangible assets								374.6
Other assets								25.1
Total assets acquired								1,220.8
Identifiable indefinite-lived intangible assets acquired										3.3	234.4	60.1	76.8
Weighted average useful life (in years)										2.0	30.0	27.0
Gross receivables acquired								152.1
Fair value of gross receivables acquired								148.2
Liabilities assumed:
Current liabilities								287.0
Other long-term liabilities								165.0
Total liabilities assumed								452.0
Noncontrolling interests								1.8
Net assets acquired								767.0
Estimated additional amortization and depreciation expense as a result of intangibles and fixed assets acquired						5.5	10.6
Elimination of interest expense related to the portion of long-term debt paid-off at the time of acquisition						17.8	11.1
Addition of interest expense related to term loans drawn in order to finance acquisition						19.0	20.3
Elimination of rent expense associated with a facility leased						2.1	2.0
Elimination of charges incurred associated with the foreign currency protection agreements to hedge the purchase price						34.6
Elimination of transaction fees associated with the acquisition						7.4
Elimination of transaction fees incurred in connection with the acquisition						5.6
Elimination of transaction fees incurred by the acquiree in connection with the acquisition						1.8
Reduction in bonding costs due to more favorable rates under senior credit facilities						5.9	5.5
Pro forma information
Revenues						4,971.1	4,502.2
Income from continuing operations attributable to SPX Corporation common shareholders						158.5	195.3
Net income attributable to SPX Corporation common shareholders						$ 188.5	$ 220.1
Income from continuing operations:
Basic (in dollars per share)						$ 3.14	$ 3.93
Diluted (in dollars per share)						$ 3.11	$ 3.88
Net income attributable to SPX Corporation common shareholders:
Basic (in dollars per share)						$ 3.73	$ 4.43
Diluted (in dollars per share)						$ 3.70	$ 4.37