Commitments and Contingencies	9 Months Ended
Jun. 30, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Lease Obligations: We lease certain land, facilities, and equipment under non-cancelable operating leases. Operating lease amounts above exclude renewal option periods, property taxes, insurance, and maintenance expenses on leased properties. Our facility leases typically provide for rental adjustments for increases in base rent (up to specific limits), property taxes, insurance, and general property maintenance that would be recorded as rent expense. Rent expense was approximately $0.6 million and $0.6 million for the three months ended June 30, 2013 and 2012, respectively and approximately $1.8 million and $2.0 million for the nine months ended June 30, 2013 and 2012, respectively. There are no off-balance sheet arrangements other than our operating leases. Capital Lease Obligations: Equipment under capital lease as of September 30, 2011 was damaged by the Thailand flood and was written off against our outstanding capital lease obligation. During fiscal year 2012, we entered into agreements with our contract manufacturer in Thailand whereby our contract manufacturer agreed to purchase equipment to rebuild certain manufacturing lines damaged by flood waters and we agreed to reimburse our contract manufacturer for the cost of the equipment out of insurance proceeds that we expected to receive. As of September 30, 2012, we capitalized the cost of our new manufacturing lines of approximately $5.2 million and recorded an equipment capital lease obligation of $4.4 million, net of equipment deposits. In December 2012, we received flood-related insurance proceeds of $4.2 million in the form of forgiveness of $2.2 million of outstanding capital lease obligations and $2.0 million of outstanding payables. In March 2013, we received the final flood-related insurance proceeds of $14.8 million in the form of a receivable of $8.2 million which we received cash payment for in April 2013, forgiveness of $3.4 million of outstanding capital lease obligations and $3.2 million of outstanding payables. See Note 9 - Impact from Thailand Flood for additional disclosures related to the impact of the Thailand flood on our operations. Asset Retirement Obligations: We have known conditional asset retirement conditions, such as certain asset decommissioning and restoration of rented facilities to be performed in the future. Our asset retirement obligations include assumptions related to renewal option periods for those facilities where we expect to extend lease terms. In future periods, the asset retirement obligation is accreted for the change in its present value and capitalized costs are depreciated over the useful life of the related assets. If the fair value of the estimated asset retirement obligation changes, an adjustment will be recorded to both the asset retirement obligation and the asset retirement capitalized cost. Revisions in estimated liabilities can result from revisions of estimated inflation rates, escalating retirement costs, and changes in the estimated timing of settling asset retirement obligations. The fair value of our asset retirement obligations were estimated by discounting projected cash flows over the estimated life of the related assets using credit adjusted risk-free rates which ranged from 3.25% to 5.78%. There were no liabilities associated with asset retirements that were settled during the nine months ended June 30, 2013. Accretion expense of $0.1 million and $0.2 million was recorded during the three and nine months ended June 30, 2013, respectively. Warranty: We generally provide a product and other warranties on our CPV-related solar cells, components, power systems, and fiber optic products. Certain parts and labor warranties from our vendors can be assigned to our customers. Our reported financial position or results of operations may be materially different under changed conditions or when using different estimates and assumptions. In the event that estimates or assumptions prove to differ from actual results, adjustments are made in subsequent periods to reflect more current information. Indemnifications: We have agreed to indemnify certain customers against claims of infringement of the intellectual property rights of others in our sales contracts with these customers. Historically, we have not paid any claims under these indemnification obligations, and we do not have any pending indemnification claims as of June 30, 2013. In March 2012, we entered into a Master Purchase Agreement with SEI, pursuant to which we agreed to sell certain assets and transfer certain obligations associated with our Fiber Optics segment. Under the terms of the Master Purchase Agreement, we have agreed to indemnify SEI for up to $3.4 million of potential claims and expenses for the two-year period following the sale and we have recorded this amount as a deferred gain on our balance sheet as of June 30, 2013 and September 30, 2012 as a result of these contingencies. In April and May 2013, we received letters from SEI asserting indemnification claims under the Master Purchase Agreement up to $1.5 million. As of August 6, 2013, there has been no resolution to these claims. See Note 1 - Description of Business in the notes to the consolidated financial statements for additional disclosures related to this asset sale. Legal Proceedings: We are subject to various legal proceedings, claims, and litigation, either asserted or unasserted that arise in the ordinary course of business. While the outcome of these matters is currently not determinable, we do not expect the resolution of these matters will have a material adverse effect on our business, financial position, results of operations, or cash flows. However, the results of these matters cannot be predicted with certainty. Professional legal fees are expensed when incurred. We accrue for contingent losses when such losses are probable and reasonably estimable. In the event that estimates or assumptions prove to differ from actual results, adjustments are made in subsequent periods to reflect more current information. Should we fail to prevail in any legal matter or should several legal matters be resolved against the Company in the same reporting period, then the financial results of that particular reporting period could be materially affected. a) Intellectual Property Lawsuits We protect our proprietary technology by applying for patents where appropriate and, in other cases, by preserving the technology, related know-how and information as trade secrets. The success and competitive position of our product lines are impacted by our ability to obtain intellectual property protection for our research and development efforts. We have, from time to time, exchanged correspondence with third parties regarding the assertion of patent or other intellectual property rights in connection with certain of our products and processes. b) Avago-related Litigation On December 5, 2008, we were served with a complaint by Avago Technologies filed in the United States District Court for the Northern District of California, San Jose Division alleging infringement of two patents by our VCSEL products. (Avago Technologies Singapore et al., EMCORE Corporation, et al., Case No.: C08-5394 EMC) (the “N.D. CA Patent Case”). This case was stayed and recommenced following completion of the ITC case described below. In April 2012, Avago amended its complaint to include additional patents and claims. Avago and the Company agreed to mediate, and as a result of that mediation held on May 10, 2012, the Company and Avago agreed to a confidential settlement agreement for a one-time payment by the Company in exchange for a full release of all claims against the Company relating to the N.D. CA Patent Case, including claims made in the amended complaint. On March 5, 2009, we were notified that, based on a complaint filed by Avago alleging the same patent infringement that formed the basis of the complaint previously filed in the Northern District of California, the U.S. International Trade Commission (the “ITC”) had determined to begin an investigation titled “In the Matter of Certain Optoelectronic Devices, Components Thereof and Products Containing the Same”, Inv. No. 337-TA-669. This matter was tried before an administrative law judge of the ITC in November 2009. On July 12, 2010, the ITC issued its final determination, as well as a limited exclusion order and cease and desist order directed to our infringing products which prohibits importation of those products into the United States. Those remedial orders were reviewed by the President of the United States and his decision to approve those orders was issued on September 10, 2010, thereby prohibiting further importation of the infringing products. We appealed the ITC's decision, and on November 14, 2011, the Court of Appeals affirmed the ITC's determination. c) Green and Gold-related litigation On December 23, 2008, Plaintiffs Maurice Prissert and Claude Prissert filed a purported stockholder class action (the “Prissert Class Action”) pursuant to Federal Rule of Civil Procedure 23 allegedly on behalf of a class of Company shareholders against the Company and certain of its present and former directors and officers (the “Individual Defendants”) in the United States District Court for the District of New Mexico captioned, Maurice Prissert and Claude Prissert v. EMCORE Corporation, Adam Gushard, Hong Q. Hou, Reuben F. Richards, Jr., David Danzilio and Thomas Werthan, Case No. 1:08cv1190 (D.N.M.). The Complaint alleges that the Company and the Individual Defendants violated certain provisions of the federal securities laws, including Section 10(b) of the Exchange Act, arising out of the Company's disclosure regarding its customer Green and Gold Energy (“GGE”) and the associated backlog of GGE orders with the Company's Photovoltaics business segment. The Complaint in the Prissert Class Action seeks, among other things, an unspecified amount of compensatory damages and other costs and expenses associated with the maintenance of the action. On or about February 12, 2009, a second purported stockholder class action (Mueller v. EMCORE Corporation et al., Case No. 1:09cv 133 (D.N.M.)) (the “Mueller Class Action”), together with the Prissert Class Action, the “Class Actions”) was filed in the United States District Court for the District of New Mexico against the same defendants named in the Prissert Class Action, based on substantially the same facts and circumstances, containing substantially the same allegations and seeking substantially the same relief. On September 25, 2009, the court issued an order consolidating both the Prissert and Mueller class actions into one consolidated proceeding, but denied plaintiffs motions for appointment of a lead plaintiff or lead plaintiff's counsel. On July 15, 2010, the court appointed IBEW Local Union No. 58 Annuity Fund to serve as lead plaintiff (“IBEW”), but denied, without prejudice, IBEW's motion to appoint lead counsel. On August 24, 2010, IBEW filed a renewed motion for appointment as lead plaintiff and for approval of its selection of counsel. IBEW filed a renewed motion for appointment of counsel on May 13, 2011 which we did not oppose. By Order dated September 30, 2011, the court appointed counsel to act on behalf of the purported class. On November 14, 2011, the plaintiffs filed a Consolidated Amended Complaint, again alleging violations of the federal securities laws arising out of the Company's disclosure regarding its customer GGE and the associated backlog of GGE orders with the Company's Photovoltaics business segment (the “Amended Complaint”). We filed a motion to dismiss the Amended Complaint on January 9, 2012, and on September 28, 2012, the court ruled in our favor. On November 9, 2012, we entered into a stipulation and agreement with the lead class representative, pursuant to which the parties agreed to release each other from all claims related to the matter and not to appeal the dismissal of the Amended Complaint, effectively ending this litigation. On January 23, 2009, Plaintiff James E. Stearns filed a purported stockholder derivative action (the “Stearns Derivative Action”) on behalf of the Company against the Individual Defendants, as well as the Company as nominal defendant in the Superior Court of New Jersey, Atlantic County, Chancery Division (James E. Stearns, derivatively on behalf of EMCORE Corporation v. Thomas J. Russell, Robert Bogomolny, Charles Scott, John Gillen, Reuben F. Richards, Jr., Hong Q. Hou, Adam Gushard, David Danzilio and Thomas Werthan, Case No. Atl-C-10-09). This action is based on essentially the same factual contentions as the Prissert Class Action, and alleges that the Individual Defendants engaged in improprieties and violations of law in connection with the reporting of the GGE backlog. The Stearns Derivative Action seeks several forms of relief, allegedly on behalf of the Company, including, among other things, damages, equitable relief, corporate governance reforms, an accounting of, rescission of, restitution of, and costs and disbursements of the lawsuit. On March 11, 2009, Plaintiff Gary Thomas filed a second purported shareholder derivative action (the “Thomas Derivative Action”; together with the Stearns Derivative Action, the “Derivative Actions”) in the U.S. District Court for the District of New Mexico against the Company and certain of the Individual Defendants (Gary Thomas, derivatively on behalf of EMCORE Corporation v. Thomas J. Russell, Robert Bogomolny, Charles Scott, John Gillen, Reuben F. Richards, Jr., Hong Q. Hou, and EMCORE Corporation, Case No. 1.09-cv-00236, (D.N.M.)). The Thomas Derivative Action makes substantially the same allegations as the Stearns Derivative Action and seeks essentially the same relief. The Stearns Derivative Action and the Thomas Derivative action were consolidated before a single judge in Somerset County, New Jersey. Based on the dismissal of the Class Actions, on December 5, 2012, we entered into a stipulation and agreement whereby the plaintiffs in the Derivative Actions agreed to dismiss their claims with prejudice, effectively ending the Derivative Actions and the last remaining Green and Gold-related litigation. No payment was made in connection with the dismissal of the Class Actions or the Derivative Actions.

Commitments and Contingencies

Operating Lease Obligations: We lease certain land, facilities, and equipment under non-cancelable operating leases. Operating lease amounts above exclude renewal option periods, property taxes, insurance, and maintenance expenses on leased properties. Our facility leases typically provide for rental adjustments for increases in base rent (up to specific limits), property taxes, insurance, and general property maintenance that would be recorded as rent expense. Rent expense was approximately $0.6 million and $0.6 million for the three months ended June 30, 2013 and 2012, respectively and approximately $1.8 million and $2.0 million for the nine months ended June 30, 2013 and 2012, respectively. There are no off-balance sheet arrangements other than our operating leases.

Capital Lease Obligations: Equipment under capital lease as of September 30, 2011 was damaged by the Thailand flood and was written off against our outstanding capital lease obligation. During fiscal year 2012, we entered into agreements with our contract manufacturer in Thailand whereby our contract manufacturer agreed to purchase equipment to rebuild certain manufacturing lines damaged by flood waters and we agreed to reimburse our contract manufacturer for the cost of the equipment out of insurance proceeds that we expected to receive. As of September 30, 2012, we capitalized the cost of our new manufacturing lines of approximately $5.2 million and recorded an equipment capital lease obligation of $4.4 million, net of equipment deposits. In December 2012, we received flood-related insurance proceeds of $4.2 million in the form of forgiveness of $2.2 million of outstanding capital lease obligations and $2.0 million of outstanding payables. In March 2013, we received the final flood-related insurance proceeds of $14.8 million in the form of a receivable of $8.2 million which we received cash payment for in April 2013, forgiveness of $3.4 million of outstanding capital lease obligations and $3.2 million of outstanding payables. See Note 9 - Impact from Thailand Flood for additional disclosures related to the impact of the Thailand flood on our operations.

Asset Retirement Obligations: We have known conditional asset retirement conditions, such as certain asset decommissioning and restoration of rented facilities to be performed in the future. Our asset retirement obligations include assumptions related to renewal option periods for those facilities where we expect to extend lease terms. In future periods, the asset retirement obligation is accreted for the change in its present value and capitalized costs are depreciated over the useful life of the related assets. If the fair value of the estimated asset retirement obligation changes, an adjustment will be recorded to both the asset retirement obligation and the asset retirement capitalized cost. Revisions in estimated liabilities can result from revisions of estimated inflation rates, escalating retirement costs, and changes in the estimated timing of settling asset retirement obligations. The fair value of our asset retirement obligations were estimated by discounting projected cash flows over the estimated life of the related assets using credit adjusted risk-free rates which ranged from 3.25% to 5.78%. There were no liabilities associated with asset retirements that were settled during the nine months ended June 30, 2013. Accretion expense of $0.1 million and $0.2 million was recorded during the three and nine months ended June 30, 2013, respectively.

Warranty: We generally provide a product and other warranties on our CPV-related solar cells, components, power systems, and fiber optic products. Certain parts and labor warranties from our vendors can be assigned to our customers. Our reported financial position or results of operations may be materially different under changed conditions or when using different estimates and assumptions. In the event that estimates or assumptions prove to differ from actual results, adjustments are made in subsequent periods to reflect more current information.

Indemnifications: We have agreed to indemnify certain customers against claims of infringement of the intellectual property rights of others in our sales contracts with these customers. Historically, we have not paid any claims under these indemnification obligations, and we do not have any pending indemnification claims as of June 30, 2013. In March 2012, we entered into a Master Purchase Agreement with SEI, pursuant to which we agreed to sell certain assets and transfer certain obligations associated with our Fiber Optics segment. Under the terms of the Master Purchase Agreement, we have agreed to indemnify SEI for up to $3.4 million of potential claims and expenses for the two-year period following the sale and we have recorded this amount as a deferred gain on our balance sheet as of June 30, 2013 and September 30, 2012 as a result of these contingencies. In April and May 2013, we received letters from SEI asserting indemnification claims under the Master Purchase Agreement up to $1.5 million. As of August 6, 2013, there has been no resolution to these claims. See Note 1 - Description of Business in the notes to the consolidated financial statements for additional disclosures related to this asset sale.

Legal Proceedings: We are subject to various legal proceedings, claims, and litigation, either asserted or unasserted that arise in the ordinary course of business. While the outcome of these matters is currently not determinable, we do not expect the resolution of these matters will have a material adverse effect on our business, financial position, results of operations, or cash flows. However, the results of these matters cannot be predicted with certainty. Professional legal fees are expensed when incurred. We accrue for contingent losses when such losses are probable and reasonably estimable. In the event that estimates or assumptions prove to differ from actual results, adjustments are made in subsequent periods to reflect more current information. Should we fail to prevail in any legal matter or should several legal matters be resolved against the Company in the same reporting period, then the financial results of that particular reporting period could be materially affected.

a) Intellectual Property Lawsuits

We protect our proprietary technology by applying for patents where appropriate and, in other cases, by preserving the technology, related know-how and information as trade secrets. The success and competitive position of our product lines are impacted by our ability to obtain intellectual property protection for our research and development efforts. We have, from time to time, exchanged correspondence with third parties regarding the assertion of patent or other intellectual property rights in connection with certain of our products and processes.

b) Avago-related Litigation

On December 5, 2008, we were served with a complaint by Avago Technologies filed in the United States District Court for the Northern District of California, San Jose Division alleging infringement of two patents by our VCSEL products. (Avago Technologies Singapore et al., EMCORE Corporation, et al., Case No.: C08-5394 EMC) (the “N.D. CA Patent Case”). This case was stayed and recommenced following completion of the ITC case described below. In April 2012, Avago amended its complaint to include additional patents and claims. Avago and the Company agreed to mediate, and as a result of that mediation held on May 10, 2012, the Company and Avago agreed to a confidential settlement agreement for a one-time payment by the Company in exchange for a full release of all claims against the Company relating to the N.D. CA Patent Case, including claims made in the amended complaint.

On March 5, 2009, we were notified that, based on a complaint filed by Avago alleging the same patent infringement that formed the basis of the complaint previously filed in the Northern District of California, the U.S. International Trade Commission (the “ITC”) had determined to begin an investigation titled “In the Matter of Certain Optoelectronic Devices, Components Thereof and Products Containing the Same”, Inv. No. 337-TA-669. This matter was tried before an administrative law judge of the ITC in November 2009.

On July 12, 2010, the ITC issued its final determination, as well as a limited exclusion order and cease and desist order directed to our infringing products which prohibits importation of those products into the United States. Those remedial orders were reviewed by the President of the United States and his decision to approve those orders was issued on September 10, 2010, thereby prohibiting further importation of the infringing products. We appealed the ITC's decision, and on November 14, 2011, the Court of Appeals affirmed the ITC's determination.

c) Green and Gold-related litigation

On December 23, 2008, Plaintiffs Maurice Prissert and Claude Prissert filed a purported stockholder class action (the “Prissert Class Action”) pursuant to Federal Rule of Civil Procedure 23 allegedly on behalf of a class of Company shareholders against the Company and certain of its present and former directors and officers (the “Individual Defendants”) in the United States District Court for the District of New Mexico captioned, Maurice Prissert and Claude Prissert v. EMCORE Corporation, Adam Gushard, Hong Q. Hou, Reuben F. Richards, Jr., David Danzilio and Thomas Werthan, Case No. 1:08cv1190 (D.N.M.). The Complaint alleges that the Company and the Individual Defendants violated certain provisions of the federal securities laws, including Section 10(b) of the Exchange Act, arising out of the Company's disclosure regarding its customer Green and Gold Energy (“GGE”) and the associated backlog of GGE orders with the Company's Photovoltaics business segment. The Complaint in the Prissert Class Action seeks, among other things, an unspecified amount of compensatory damages and other costs and expenses associated with the maintenance of the action. On or about February 12, 2009, a second purported stockholder class action (Mueller v. EMCORE Corporation et al., Case No. 1:09cv 133 (D.N.M.)) (the “Mueller Class Action”), together with the Prissert Class Action, the “Class Actions”) was filed in the United States District Court for the District of New Mexico against the same defendants named in the Prissert Class Action, based on substantially the same facts and circumstances, containing substantially the same allegations and seeking substantially the same relief.

On September 25, 2009, the court issued an order consolidating both the Prissert and Mueller class actions into one consolidated proceeding, but denied plaintiffs motions for appointment of a lead plaintiff or lead plaintiff's counsel. On July 15, 2010, the court appointed IBEW Local Union No. 58 Annuity Fund to serve as lead plaintiff (“IBEW”), but denied, without prejudice, IBEW's motion to appoint lead counsel. On August 24, 2010, IBEW filed a renewed motion for appointment as lead plaintiff and for approval of its selection of counsel. IBEW filed a renewed motion for appointment of counsel on May 13, 2011 which we did not oppose. By Order dated September 30, 2011, the court appointed counsel to act on behalf of the purported class. On November 14, 2011, the plaintiffs filed a Consolidated Amended Complaint, again alleging violations of the federal securities laws arising out of the Company's disclosure regarding its customer GGE and the associated backlog of GGE orders with the Company's Photovoltaics business segment (the “Amended Complaint”). We filed a motion to dismiss the Amended Complaint on January 9, 2012, and on September 28, 2012, the court ruled in our favor. On November 9, 2012, we entered into a stipulation and agreement with the lead class representative, pursuant to which the parties agreed to release each other from all claims related to the matter and not to appeal the dismissal of the Amended Complaint, effectively ending this litigation.

On January 23, 2009, Plaintiff James E. Stearns filed a purported stockholder derivative action (the “Stearns Derivative Action”) on behalf of the Company against the Individual Defendants, as well as the Company as nominal defendant in the Superior Court of New Jersey, Atlantic County, Chancery Division (James E. Stearns, derivatively on behalf of EMCORE Corporation v. Thomas J. Russell, Robert Bogomolny, Charles Scott, John Gillen, Reuben F. Richards, Jr., Hong Q. Hou, Adam Gushard, David Danzilio and Thomas Werthan, Case No. Atl-C-10-09). This action is based on essentially the same factual contentions as the Prissert Class Action, and alleges that the Individual Defendants engaged in improprieties and violations of law in connection with the reporting of the GGE backlog. The Stearns Derivative Action seeks several forms of relief, allegedly on behalf of the Company, including, among other things, damages, equitable relief, corporate governance reforms, an accounting of, rescission of, restitution of, and costs and disbursements of the lawsuit.

On March 11, 2009, Plaintiff Gary Thomas filed a second purported shareholder derivative action (the “Thomas Derivative Action”; together with the Stearns Derivative Action, the “Derivative Actions”) in the U.S. District Court for the District of New Mexico against the Company and certain of the Individual Defendants (Gary Thomas, derivatively on behalf of EMCORE Corporation v. Thomas J. Russell, Robert Bogomolny, Charles Scott, John Gillen, Reuben F. Richards, Jr., Hong Q. Hou, and EMCORE Corporation, Case No. 1.09-cv-00236, (D.N.M.)). The Thomas Derivative Action makes substantially the same allegations as the Stearns Derivative Action and seeks essentially the same relief.

The Stearns Derivative Action and the Thomas Derivative action were consolidated before a single judge in Somerset County, New Jersey.

Based on the dismissal of the Class Actions, on December 5, 2012, we entered into a stipulation and agreement whereby the plaintiffs in the Derivative Actions agreed to dismiss their claims with prejudice, effectively ending the Derivative Actions and the last remaining Green and Gold-related litigation. No payment was made in connection with the dismissal of the Class Actions or the Derivative Actions.