Summary Of Significant Accounting Policies And Recent Accounting Standards (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty reserve	$ 1,600,000		$ 1,600,000		$ 1,700,000
Pre-tax share-based compensation expense	700,000	$ 600,000	1,300,000	$ 900,000
Asset impairment charges	$ 0	$ 0	$ 0	$ 0
Purchased Software And Software Development Costs [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Finite-lived intangible assets, useful life			5 years
Maximum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Estimated useful lives			30 years
Maximum [Member] | Patents And Licensing Agreements [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Finite-lived intangible assets, useful life			5 years
Minimum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Estimated useful lives			3 years
Minimum [Member] | Patents And Licensing Agreements [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Finite-lived intangible assets, useful life			3 years
Distributed Generation, Switchgear And Utility Infrastructure Equipment [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			1 year
LED Lighting-Based Products [Member] | Maximum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			10 years
LED Lighting-Based Products [Member] | Minimum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			5 years
Defects In Material And Workmanship [Member] | Maximum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			5 years
Defects In Material And Workmanship [Member] | Minimum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			1 year
Declines In Power Performance [Member] | Maximum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			20 years
Declines In Power Performance [Member] | Minimum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			10 years
Functionality Of Solar Panels [Member] | Maximum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			25 years
Functionality Of Solar Panels [Member] | Minimum [Member]
Summary Of Significant Accounting Policies And Recent Accounting Standards [Line Items]
Warranty period			15 years