Divestitures (Details) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2012 Tennant CEE GmbH and OOO Tennant [Member] USD ($)	Sep. 30, 2012 Tennant CEE GmbH and OOO Tennant [Member] EUR (€)	Jul. 31, 2012 Tennant CEE GmbH and OOO Tennant [Member] USD ($)
Divestitures [Line Items]
Date of Divestiture					Jul. 31, 2012	Jul. 31, 2012
Total Selling Price						€ 6,166
Cash Received as Part of Selling Price					1,014	815
Total Amount of Installment Payments to be Received Quarterly in 2013					2,738	2,126
Total Amount of Installment Payments to be Received on First, Second and Third Anniversary Dates					4,153	3,225
Gain on Sale of Business	784	0	784	0	784
Assets and Liabilities Divested [Abstract]
Accounts Receivable							4,398
Inventory							4,271
Other Current Assets							87
Current Assets							8,756
Property, Plant and Equipment							170
Total Assets Divested							8,926
Current Liabilities							1,121
Total Liabilities Divested							1,121
Net Assets Divested							$ 7,805