Organization and Significant Accounting Policies	9 Months Ended
Sep. 30, 2016
Accounting Policies [Abstract]
Organization and Significant Accounting Policies	Organization and Significant Accounting Policies Organization We are a biopharmaceutical company committed to discovering, developing and commercializing both small-molecule and protein therapeutics for large-market as well as orphan indications targeting inflammation, coagulopathies and disorders of the central nervous system. Our first drug product, OMIDRIA, is approved by the United States (U.S.) Food and Drug Administration (FDA) for use during cataract surgery or intraocular lens replacement. We broadly launched OMIDRIA in the U.S. in April 2015. Basis of Presentation Our condensed consolidated financial statements include the financial position and results of operations of Omeros Corporation (Omeros) and our wholly owned subsidiaries. All inter-company transactions have been eliminated and we have determined we operate in one segment. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The information as of September 30, 2016 and for the three and nine months ended September 30, 2016 and 2015 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2015 has been derived from our audited financial statements but does not include all of the information and footnotes required by GAAP for audited annual financial information. The accompanying unaudited condensed consolidated financial statements and related notes thereto should be read in conjunction with the audited consolidated financial statements and related notes thereto that are included in our Annual Report on Form 10-K for the year ended December 31, 2015, which was filed with the U.S. Securities and Exchange Commission (SEC) on March 15, 2016. Product Sales, Net We record revenue from OMIDRIA sales when the product is delivered to our wholesalers. Product sales are recorded net of estimated chargebacks and rebates, wholesaler distribution fees and estimated product returns. Accruals or allowances are established for these deductions when revenue is recognized, and actual amounts incurred are offset against the applicable accruals and allowances. We reflect each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability, depending on how the accrual or allowance is settled. Product sales to wholesalers are not recorded if we determine that the wholesaler’s on-hand OMIDRIA inventory, based on inventory information we regularly receive from our wholesalers, exceeds approximately eight weeks of projected demand. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant items subject to such estimates include revenue recognition, fair market value of investments, stock-based compensation expense and accruals for clinical trials and contingencies. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances; however, actual results could differ from these estimates. Liquidity and Capital Resources As of September 30, 2016, we had $47.4 million in cash, cash equivalents and short-term investments. In addition, we had $10.0 million in restricted cash and investments that was required to be maintained in depository and investment accounts with East West Bank (EWB) pursuant to the Loan and Security Agreement (the Oxford/EWB Loan Agreement) entered into in December 2015 with Oxford Finance LLC (Oxford) and EWB, as well as $679,000 to secure a letter of credit for the Omeros Building lease and $156,000 to secure a letter of credit for fleet vehicles used by our OMIDRIA sales force. On October 26, 2016, we entered into a six-year term Term Loan Agreement (the CRG Loan Agreement) with CRG Servicing LLC (CRG), as administrative agent and collateral agent, the lenders named therein (the Lenders) and nura, inc. as subsidiary guarantor. We initially borrowed $80.0 million and may borrow an additional $45.0 million in two tranches of $25.0 million and $20.0 million contingent on achievement of certain conditions including either satisfying minimum OMIDRIA net revenues or minimum average market capitalization on or before each of June 30, 2017 and December 31, 2017, respectively. The CRG Loan Agreement accrues interest at 12.25% (4.0% of which can be deferred at our option by adding such amount to the aggregate principal loan amount) and is interest-only for a minimum of four years (through December 31, 2020) and, subject to the achievement of certain milestones, potentially for the full six-year term. The CRG Loan Agreement requires us to maintain $5.0 million in cash and cash equivalents at all times. We used $75.7 million of the initial borrowing to repay all of the amounts owed by us under the then-outstanding Oxford/EWB Loan Agreement. After deducting the loan initiation costs and related fees, and considering the reduction of the restricted cash requirement associated with the previously outstanding Oxford/EWB Loan Agreement, we gained access to approximately $8.0 million in net additional cash available for operations upon funding. While we have improved our cash position, improved our access to future debt financing upon achievement of the specific milestones and reduced our near-term debt service funding requirements by entering into the CRG Loan Agreement, we expect to continue to incur losses until such time as OMIDRIA product sales, corporate partnerships and/or licensing revenues from products or programs are adequate to support our ongoing operating expenses and debt service, including maintenance of any restricted cash and investments, if required. We are unable to predict if or when this may occur, and until it does occur, we will need to continue to raise additional funds through public or private equity securities sales, including under our At Market Issuance Sales Agreement (the ATM Agreement) with JonesTrading Institutional Services LLC (JonesTrading) (see Note 9 for further detail), through the incurrence of additional debt, through corporate partnerships, through asset sales or through the pursuit of collaborations and licensing arrangements related to certain of our products or programs. These conditions raise a substantial doubt about our ability to continue as a going concern. If we are unable to become cash-flow positive or to raise additional capital as and when needed, or upon acceptable terms, such failure would have a significant negative impact on our financial condition. The accompanying unaudited condensed consolidated financial statements have been prepared on a going-concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The accompanying unaudited condensed consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from uncertainty related to our ability to continue as a going concern. Recent Accounting Pronouncements In August 2014, FASB issued ASU No. 2014-15 related to disclosure of an entity’s ability to continue as a going concern. This standard requires management to evaluate whether substantial doubt exists regarding the entity’s ability to continue as a going concern at each reporting period for a duration of one year after the date the financial statements are issued or available to be issued and to provide related footnote disclosures. This standard must be applied prospectively and is effective for interim and annual periods ending after December 15, 2016. We are monitoring for any conditions and events that could raise substantial doubt about our ability to continue as a going concern. The evaluation of the significance of those conditions and events and the related impact upon our disclosures, if applicable, will be disclosed in our annual financial statements for the year ended December 31, 2016. In February 2016, FASB issued ASU 2016-02 related to lease accounting. This standard requires lessees to recognize a right-of-use asset and a lease liability for most leases. This standard must be applied using a modified retrospective transition and is effective for all annual and interim periods beginning after December 15, 2018. Earlier adoption is permitted. We are evaluating how this new standard will impact the presentation of our financial statements and related disclosures. In March 2016, FASB issued ASU 2016-08 related to revenue recognition. This standard is an amendment to ASU 2014-09 relating to revenue from contracts with customers. This amendment clarifies an entity’s revenue recognition for a performance obligation based on principal versus agent considerations. This standard has the same effective date and transition requirements as ASU 2014-09, as amended, which requires that the guidance must be applied retroactively to each prior reporting period presented or retrospectively with the cumulative effect of applying the standard recognized in the period adopted. As amended, the standard is effective for interim and annual periods beginning after December 15, 2017 and cannot be adopted before the original effective date, which was for periods beginning after December 15, 2016. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted. In March 2016, FASB issued ASU 2016-09 that changes the accounting for certain aspects of share-based payments to employees. The guidance requires the recognition of the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid in capital pools. The guidance also allows for the employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting and for making a policy election to account for forfeitures as they occur rather than on an estimated basis. The guidance is effective for interim and annual periods beginning after December 15, 2016 with early adoption permitted. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted and the timing of adoption. In April and May 2016, FASB issued ASU 2016-10 and ASU 2016-12, respectively. Both standards are amendments to ASU 2014-09 related to revenue from contracts with customers. ASU 2016-10 clarifies an entity’s revenue recognition when identifying performance obligations and licensing. ASU 2016-12 clarifies the objective of the collectibility criterion, one of the five steps of ASU 2014-09. This amendment also establishes practical expedients for sales-tax considerations and contract modifications. Both standards have the same effective date and transition requirements as ASU 2014-09, as amended. We are currently evaluating the impact that these standards may have on our financial statements once they are adopted. In August 2016, FASB issued ASU 2016-15 related to the Cash Flow Statement. This guidance clarifies how certain cash receipts and cash payments are classified on the statement of cash flows. The guidance is effective for interim and annual periods beginning after December 15, 2017 with early adoption permitted. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted and the timing of adoption.

Organization and Significant Accounting Policies

Organization

We are a biopharmaceutical company committed to discovering, developing and commercializing both small-molecule and protein therapeutics for large-market as well as orphan indications targeting inflammation, coagulopathies and disorders of the central nervous system. Our first drug product, OMIDRIA, is approved by the United States (U.S.) Food and Drug Administration (FDA) for use during cataract surgery or intraocular lens replacement. We broadly launched OMIDRIA in the U.S. in April 2015.

Basis of Presentation

Our condensed consolidated financial statements include the financial position and results of operations of Omeros Corporation (Omeros) and our wholly owned subsidiaries. All inter-company transactions have been eliminated and we have determined we operate in one segment. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The information as of September 30, 2016 and for the three and nine months ended September 30, 2016 and 2015 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2015 has been derived from our audited financial statements but does not include all of the information and footnotes required by GAAP for audited annual financial information.

The accompanying unaudited condensed consolidated financial statements and related notes thereto should be read in conjunction with the audited consolidated financial statements and related notes thereto that are included in our Annual Report on Form 10-K for the year ended December 31, 2015, which was filed with the U.S. Securities and Exchange Commission (SEC) on March 15, 2016.

Product Sales, Net

We record revenue from OMIDRIA sales when the product is delivered to our wholesalers.

Product sales are recorded net of estimated chargebacks and rebates, wholesaler distribution fees and estimated product returns. Accruals or allowances are established for these deductions when revenue is recognized, and actual amounts incurred are offset against the applicable accruals and allowances. We reflect each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability, depending on how the accrual or allowance is settled. Product sales to wholesalers are not recorded if we determine that the wholesaler’s on-hand OMIDRIA inventory, based on inventory information we regularly receive from our wholesalers, exceeds approximately eight weeks of projected demand.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant items subject to such estimates include revenue recognition, fair market value of investments, stock-based compensation expense and accruals for clinical trials and contingencies. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances; however, actual results could differ from these estimates.

Liquidity and Capital Resources

As of September 30, 2016, we had $47.4 million in cash, cash equivalents and short-term investments. In addition, we had $10.0 million in restricted cash and investments that was required to be maintained in depository and investment accounts with East West Bank (EWB) pursuant to the Loan and Security Agreement (the Oxford/EWB Loan Agreement) entered into in December 2015 with Oxford Finance LLC (Oxford) and EWB, as well as $679,000 to secure a letter of credit for the Omeros Building lease and $156,000 to secure a letter of credit for fleet vehicles used by our OMIDRIA sales force.

On October 26, 2016, we entered into a six-year term Term Loan Agreement (the CRG Loan Agreement) with CRG Servicing LLC (CRG), as administrative agent and collateral agent, the lenders named therein (the Lenders) and nura, inc. as subsidiary guarantor. We initially borrowed $80.0 million and may borrow an additional $45.0 million in two tranches of $25.0 million and $20.0 million contingent on achievement of certain conditions including either satisfying minimum OMIDRIA net revenues or minimum average market capitalization on or before each of June 30, 2017 and December 31, 2017, respectively. The CRG Loan Agreement accrues interest at 12.25% (4.0% of which can be deferred at our option by adding such amount to the aggregate principal loan amount) and is interest-only for a minimum of four years (through December 31, 2020) and, subject to the achievement of certain milestones, potentially for the full six-year term. The CRG Loan Agreement requires us to maintain $5.0 million in cash and cash equivalents at all times.

We used $75.7 million of the initial borrowing to repay all of the amounts owed by us under the then-outstanding Oxford/EWB Loan Agreement. After deducting the loan initiation costs and related fees, and considering the reduction of the restricted cash requirement associated with the previously outstanding Oxford/EWB Loan Agreement, we gained access to approximately $8.0 million in net additional cash available for operations upon funding.

While we have improved our cash position, improved our access to future debt financing upon achievement of the specific milestones and reduced our near-term debt service funding requirements by entering into the CRG Loan Agreement, we expect to continue to incur losses until such time as OMIDRIA product sales, corporate partnerships and/or licensing revenues from products or programs are adequate to support our ongoing operating expenses and debt service, including maintenance of any restricted cash and investments, if required. We are unable to predict if or when this may occur, and until it does occur, we will need to continue to raise additional funds through public or private equity securities sales, including under our At Market Issuance Sales Agreement (the ATM Agreement) with JonesTrading Institutional Services LLC (JonesTrading) (see Note 9 for further detail), through the incurrence of additional debt, through corporate partnerships, through asset sales or through the pursuit of collaborations and licensing arrangements related to certain of our products or programs. These conditions raise a substantial doubt about our ability to continue as a going concern. If we are unable to become cash-flow positive or to raise additional capital as and when needed, or upon acceptable terms, such failure would have a significant negative impact on our financial condition.

The accompanying unaudited condensed consolidated financial statements have been prepared on a going-concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The accompanying unaudited condensed consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from uncertainty related to our ability to continue as a going concern.

Recent Accounting Pronouncements

In August 2014, FASB issued ASU No. 2014-15 related to disclosure of an entity’s ability to continue as a going concern. This standard requires management to evaluate whether substantial doubt exists regarding the entity’s ability to continue as a going concern at each reporting period for a duration of one year after the date the financial statements are issued or available to be issued and to provide related footnote disclosures. This standard must be applied prospectively and is effective for interim and annual periods ending after December 15, 2016. We are monitoring for any conditions and events that could raise substantial doubt about our ability to continue as a going concern. The evaluation of the significance of those conditions and events and the related impact upon our disclosures, if applicable, will be disclosed in our annual financial statements for the year ended December 31, 2016.

In February 2016, FASB issued ASU 2016-02 related to lease accounting. This standard requires lessees to recognize a right-of-use asset and a lease liability for most leases. This standard must be applied using a modified retrospective transition and is effective for all annual and interim periods beginning after December 15, 2018. Earlier adoption is permitted. We are evaluating how this new standard will impact the presentation of our financial statements and related disclosures.

In March 2016, FASB issued ASU 2016-08 related to revenue recognition. This standard is an amendment to ASU 2014-09 relating to revenue from contracts with customers. This amendment clarifies an entity’s revenue recognition for a performance obligation based on principal versus agent considerations. This standard has the same effective date and transition requirements as ASU 2014-09, as amended, which requires that the guidance must be applied retroactively to each prior reporting period presented or retrospectively with the cumulative effect of applying the standard recognized in the period adopted. As amended, the standard is effective for interim and annual periods beginning after December 15, 2017 and cannot be adopted before the original effective date, which was for periods beginning after December 15, 2016. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted.

In March 2016, FASB issued ASU 2016-09 that changes the accounting for certain aspects of share-based payments to employees. The guidance requires the recognition of the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid in capital pools. The guidance also allows for the employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting and for making a policy election to account for forfeitures as they occur rather than on an estimated basis. The guidance is effective for interim and annual periods beginning after December 15, 2016 with early adoption permitted. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted and the timing of adoption.

In April and May 2016, FASB issued ASU 2016-10 and ASU 2016-12, respectively. Both standards are amendments to ASU 2014-09 related to revenue from contracts with customers. ASU 2016-10 clarifies an entity’s revenue recognition when identifying performance obligations and licensing. ASU 2016-12 clarifies the objective of the collectibility criterion, one of the five steps of ASU 2014-09. This amendment also establishes practical expedients for sales-tax considerations and contract modifications. Both standards have the same effective date and transition requirements as ASU 2014-09, as amended. We are currently evaluating the impact that these standards may have on our financial statements once they are adopted.

In August 2016, FASB issued ASU 2016-15 related to the Cash Flow Statement. This guidance clarifies how certain cash receipts and cash payments are classified on the statement of cash flows. The guidance is effective for interim and annual periods beginning after December 15, 2017 with early adoption permitted. We are currently evaluating the impact that this standard may have on our financial statements once it is adopted and the timing of adoption.