Suncore Joint Venture (Details) (USD $)	1 Months Ended	3 Months Ended		6 Months Ended				0 Months Ended		1 Months Ended		3 Months Ended		6 Months Ended
	Aug. 31, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Nov. 30, 2011	Jul. 30, 2010	Aug. 06, 2012 CPV	Mar. 31, 2013 CPV	Mar. 31, 2013 Emcore Solar New Mexico	Sep. 30, 2012 Emcore Solar New Mexico	Mar. 31, 2013 Suncore	Mar. 31, 2012 Suncore	Mar. 31, 2013 Suncore	Mar. 31, 2012 Suncore	Mar. 31, 2013 Foreign Tax Authority
Initital Registered Capital:
Equity method investment, initial registered capital, total entity							$ 30,000,000
Equity method investment, initial registered capital, equity partner							18,000,000
Equity method investment, initial registered capital, EMCORE							12,000,000
Basis Difference:
Equity method investment, basis difference, consulting fee, amount received							8,500,000
Capital Distributions:
Equity method investment, deemed capital distribution and reinvestment, total entity				37,000,000
Equity method investment, deemed capital distribution and reinvestment, equity partner				22,200,000
Equity method investment, deemed capital distribution and reinvestment, EMCORE				14,800,000
Cash Dividends:
Equity method investment, dividend distribution, total entity				4,100,000
Equity method investment, dividend distribution, equity partner				2,500,000
Equity method investment, dividend distribution, EMCORE				1,600,000
Foreign income tax:
Foreign income tax expense on capital distributions		0	0	120,000	1,644,000											1,600,000
CPV Development Agreement:
Equity method investment, CPV development agreement, reimbursement rate	50.00%
Equity method investment, CPV development agreement, development fee rate	20.00%
Equity method investment, CPV development agreement, maximum development fee	200,000
Equity method investment, CPV development agreement, reimbursed costs, total			700,000
Equity method investment, CPV development agreement, development fees recognized			200,000
CPV Solar Cell License Agreement:
License agreement, expected proceeds over term						2,500,000
Summarized Financial Information:
Equity method investment, ownership percentage		40.00%		40.00%
Equity method investment, difference between carrying amount and underlying equity		(3,100,000)		(3,100,000)
Equity method investment		0		0						4,600,000	0
Proceeds from sale of assets								2,800,000		1,500,000
Prepaid expense and other assets, current, portion of sales price of productive assets									2,800,000
Equity method investment, revenue												$ 2,900,000	$ 200,000	$ 5,500,000	$ 1,200,000