Acquisition and Discontinued Operations (Narrative) (Details) - USD ($) $ in Millions		1 Months Ended
	Jan. 13, 2017	Apr. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 04, 2014
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Business acquisition, goodwill			$ 10.1	$ 1.1
DLW [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Contingent liability					$ 12.9
Assets removed from balance sheet					151.9
Liabilities removed from balance sheet					$ 164.8
Subsequent Event [Member] | DLW [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Settlement agreement and mutual release with administrator to settle all claims of Administrator related to insolvency for a cash payment		$ 11.8
Accounts Payable and Accrued Expenses [Member] | DLW [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Contingent liability			$ 11.9
Tectum, Inc. [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Business acquisition, purchase price	$ 31.4
Business acquisition, total fair value of tangible assets acquired, less liabilities assumed	5.9
Business acquisition, total fair value of intangible assets of amortizable customer relationships and non-amortizing brand names	16.5
Business acquisition, goodwill	$ 9.0