The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 13, 2015
Cash, Cash Equivalents, and Short-term Investments		$ 18,276
Percentage of Weighted Average Cost Inventory	44.00%	38.00%
Goodwill, Impairment Loss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Asset Retirement Obligation	832us-gaap_AssetRetirementObligation	667us-gaap_AssetRetirementObligation
Product Warranty Accrual	11,500us-gaap_ProductWarrantyAccrual	7,483us-gaap_ProductWarrantyAccrual
Foreign Currency Transaction Gain (Loss), Realized	422	433	(238)
Research and Development Expense	3,096us-gaap_ResearchAndDevelopmentExpense	3,154us-gaap_ResearchAndDevelopmentExpense	2,926us-gaap_ResearchAndDevelopmentExpense
Payments to Acquire Businesses, Net of Cash Acquired	80,797	37,500	0
Non-Domestic [Member]
Certificates of Deposit, at Carrying Value	25	32,947
Cash, Cash Equivalents, and Short-term Investments	49,233	43,560
Subsequent Event [Member] \| Tew Holdings (2012), LTD [Member]
Payments to Acquire Businesses, Net of Cash Acquired				$ 26,600
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	25 years
Maximum [Member] \| Building [Member]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] \| Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life	14 years
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	5 years
Minimum [Member] \| Building [Member]
Property, Plant and Equipment, Useful Life	25 years
Minimum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	3 years
Minimum [Member] \| Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life	2 years
Weighted Average [Member]
Finite-Lived Intangible Asset, Useful Life	16 years