Acquisitions and Goodwill Acquisition Detail (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ (32,059)	$ 0	$ 2,576
Perfect Products [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				$ 1,300
Business Combination, Contingent Consideration, Liability				30
Feeney [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				1,300
Business Combination, Contingent Consideration, Liability				100
Mattic [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				3,500
Business Combination, Contingent Consideration, Liability				$ 300