INDEBTEDNESS (Details) - USD ($)	9 Months Ended
	Sep. 28, 2019	Dec. 31, 2018
Debt
Balance at the beginning of the period	$ 381,800,000
Borrowings	191,800,000
Repayments	(192,300,000)
Other	1,600,000
Balance at the end of the period	382,900,000
Less: short-term debt	40,600,000	$ 31,900,000
Less: current maturities of long-term debt	18,500,000	18,000,000.0
Total long-term debt	323,800,000	331,900,000
Trade receivables financing arrangement
Debt
Balance at the beginning of the period	23,000,000.0
Borrowings	55,000,000.0
Repayments	(64,000,000.0)
Other	0
Balance at the end of the period	14,000,000.0
Maximum borrowing capacity	50,000,000.0
Amount of available borrowing capacity	11,800,000
Other indebtedness
Debt
Balance at the beginning of the period	4,300,000
Borrowings	4,400,000
Repayments	(700,000)
Other	1,200,000
Balance at the end of the period	9,200,000
Purchase card programs	3,800,000	2,500,000
Capital lease obligations	2,600,000	1,800,000
Revolving loans | Current Revolving SPX Facilities
Debt
Balance at the beginning of the period	6,400,000
Borrowings	132,400,000
Repayments	(118,800,000)
Other	0
Balance at the end of the period	20,000,000.0
Term loans | Current SPX Term Loan Facilities
Debt
Balance at the beginning of the period	348,100,000
Borrowings	0
Repayments	(8,800,000)
Other	400,000
Balance at the end of the period	$ 339,700,000
Initial principal amount of the term loan to be repaid annually in quarterly installments (as a percent)	1.25%
Original loan balance	$ 350,000,000.0
Debt issuance costs	1,500,000	1,900,000
Foreign credit instrument facility | Other indebtedness | China
Debt
Borrowings under line of credit	$ 2,800,000	$ 0.0