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Special Charges Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 29, 2020	Mar. 31, 2019	Jun. 28, 2020	Dec. 31, 2019
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Share-based Payment Arrangement, Expense	$ 700	$ 1,400
Professional fees to review and respond to an unsolicited tender offer to acquire the Company	2,355	153
Business Combination, Acquisition Related Costs		479
Inventories	147,175			$ 137,309
Restructuring Charges	2,883	358
Special and restructuring (recoveries) charges, net	45,175	8,200
Professional Fees	1,200
Other Nonrecurring Expense	700
Business Combination, Separately Recognized Transactions, Net Gains and Losses			$ 54,600
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction	3,200
Payments of Debt Issuance Costs	300
Proceeds from Divestiture of Businesses	200
Industrial Segment
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Restructuring Charges	2,690	290
Special and restructuring (recoveries) charges, net	53,101	8,679
Aerospace & Defense [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net	0
Advanced Flow Solutions [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Restructuring Charges	10	68
Special and restructuring (recoveries) charges, net		0
Corporate Segment [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Professional fees to review and respond to an unsolicited tender offer to acquire the Company	2,355
Business Combination, Acquisition Related Costs		479
Restructuring Charges	183	0
Special and restructuring (recoveries) charges, net	(7,926)	(479)
Instrumentation and Sampling [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net	53,200
Other Cost Saving Initiatives [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Amortization of Debt Issuance Costs	3,500
Special and restructuring (recoveries) charges, net	(2,131)
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction	3,541
Other Cost Saving Initiatives [Member] \| Industrial Segment
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net	(101)
Other Cost Saving Initiatives [Member] \| Corporate Segment [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net	(2,030)
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction	3,541
Acquisition-related Costs [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net		10,282
Acquisition-related Costs [Member] \| Corporate Segment [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Special and restructuring (recoveries) charges, net		0
Acquisition-related Costs [Member] \| Divestiture [Member] \| Industrial Segment
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Restructuring Charges		(10,282)
Acquisition-related Costs [Member] \| Divestiture [Member] \| Aerospace & Defense [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Restructuring Charges		$ 0
Phantom Share Units (PSUs) [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Share-based Payment Arrangement, Expense	(100)
Restructuring and Related Cost, Incurred Cost [Member] \| Phantom Share Units (PSUs) [Member]
Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Line Items]
Share-based Payment Arrangement, Expense	$ 100