Summary Of Significant Accounting Policies And Recent Accounting Standards (Narrative) (Details)	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2013 contract	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
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	2,000,000	$ 1,500,000
Asset impairment charges		$ 0	$ 0	$ 0	$ 0
Number of interest rate swap contracts | contract	2
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