Revenue Recognition - Product Vertcal (Details)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Product Revenue [Abstract]
Fastening Systems	23.50%	23.80%
Fluid Power	15.20%	14.50%
Specialty Chemicals	11.30%	11.90%
Cutting Tools and Abrasives	13.30%	14.90%
Electrical	11.50%	11.20%
Aftermarket Automotive Supplies	8.40%	8.50%
Safety	4.60%	4.50%
Welding and Metal Repair	1.70%	1.80%
Other Products	10.50%	9.00%
Total Products	100.00%	100.00%