Acquisitions (ITW) (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 182,185	$ 121,829	$ 68,253
OMG, Inc. | ITW Polymers Sealants North America Inc.
Business Acquisition [Line Items]
Purchase price	$ 27,400
Final working capital and other adjustments	400
Working capital	1,700
Property, plant and equipment	100
Intangibles	4,400
Goodwill	$ 21,268