Business Combinations AirSep Acquisition (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 AirSep [Member]	Jun. 30, 2013 AirSep [Member]	Aug. 30, 2012 AirSep [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired							100.00%
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net							$ 182,450
Business Acquisition, Purchase Price Allocation, Income Taxes Receivable							2,800
Debt retired							10,000
Fair value of net assets aquired							72,687
Net assets acquired:
Accounts receivable							24,280
Inventories							34,553
Prepaid expenses							615
Other current assets							3,837
Property, plant and equipment							5,342
Other assets							976
Accounts payable							(13,728)
Customer advances and billings in excess of contract revenue							(4,782)
Accrued salaries, wages and benefits							(1,837)
Other current liabilities							(254)
Current portion of warranty reserve							(10,562)
Long-term portion of warranty reserve							26,471
Net tangible assets acquired							11,969
Deferred income tax assets							9,262
Goodwill							109,763
Identifiable intangible assets							67,000
Long-term deferred tax liability							(15,544)
Standard Product Warranty Description						five years
Sales	298,266	239,939	571,914	456,045	29,855	56,869
Operating Income (Loss)	32,979	33,083	60,330	56,944	1,872	3,175
Business Acquisition, Amortization of Stepped Up Inventory Basis					2,638	2,638
Amortization expense	4,922	3,250	9,817	6,320	1,714	3,428
Management Retention Expenses and Severance Costs					$ 1,267	$ 2,204