Acquisitions (Details) - USD ($)	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017
Business Acquisition [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 58,079,000			$ 63,021,000
Accounts Receivable, Net, Current	123,411,000			127,806,000
Inventory, Net	149,716,000			152,886,000
Prepaid Expense, Current	16,577,000			16,582,000
Assets, Current	347,783,000			360,295,000
Property, Plant and Equipment, Net	88,656,000			113,079,000
Goodwill	326,851,000			347,434,000
Intangible Assets, Net (Excluding Goodwill)	239,452,000			263,764,000
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	32,668,000			32,442,000
Assets	1,062,524,000			1,142,446,000
Accounts Payable, Trade, Current	39,725,000			46,970,000
Accrued Liabilities, Current	95,494,000			99,963,000
Liabilities, Current	195,257,000			206,997,000
Other Liabilities, Noncurrent	192,041,000			223,966,000
Liabilities	642,093,000			734,217,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	420,431,000	$ 424,285,000	$ 409,568,000	408,229,000	$ 383,963,000	$ 386,799,000	$ 363,976,000	$ 341,350,000
Liabilities and Equity	1,062,524,000			$ 1,142,446,000
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Business Acquisition [Line Items]
Cash and Cash Equivalents, at Carrying Value	362,000
Accounts Receivable, Net, Current	1,796,000
Inventory, Net	11,084,000
Prepaid Expense, Current	57,000
Assets, Current	13,299,000
Property, Plant and Equipment, Net	13,793,000
Goodwill	7,304,000
Intangible Assets, Net (Excluding Goodwill)	1,810,000
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	211,000
Assets	36,417,000
Accounts Payable, Trade, Current	929,000
Accrued Liabilities, Current	1,533,000
Liabilities, Current	2,462,000
Other Liabilities, Noncurrent	1,932,000
Liabilities	4,394,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	32,023,000
Liabilities and Equity	$ 36,417,000