Basis of Presentation and Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Luna Innovations Incorporated (“we,” “Luna Innovations” or the “Company”), headquartered in Roanoke, Virginia, was incorporated in the Commonwealth of Virginia in 1990 and reincorporated in the State of Delaware in April 2003. We are a leader in advanced optical technology, providing high performance fiber optic test, measurement and control products for the telecommunications and photonics industries, and distributed fiber optic sensing solutions that measure, or "sense" the structures for industries ranging from aerospace, automotive, oil and gas, security and infrastructure. Our communications test and control products help customers test their fiber optic networks and assemblies with speed and precision in both lab and production environments, accelerating the development of fiber optic products and assuring accurate testing of optical components like photonic integrated circuits ("PICs") and coherent receivers, which are both critical elements of meeting the world’s exponentially growing demand for bandwidth. Our distributed fiber optic sensing products help designers and manufacturers more efficiently develop new and innovative products by measuring stress, strain, and temperature at a high resolution for new designs or manufacturing processes. In addition, our distributed fiber optic sensing products ensure the safety and structural integrity or operational health of critical assets in the field, by monitoring stress, strain, and vibration in large civil and industrial infrastructure such as bridges, roads, pipelines and borders. We also provide applied research services, typically under research programs funded by the U.S. government, in areas of advanced materials, sensing, and healthcare applications. Our business model is designed to accelerate the process of bringing new and innovative products to market. We use our in-house technical expertise across a range of technologies to perform applied research services for companies and for government funded projects. We continue to invest in product development and commercialization, which we anticipate will lead to increased product sales growth.
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial statements and Article 10 of Regulation S-X of the Securities Exchange Act of 1934, as amended. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for annual financial statements. The unaudited consolidated interim financial statements have been prepared on the same basis as the annual financial statements and in the opinion of management reflect all adjustments, consisting of only normal recurring accruals considered necessary to present fairly our financial position at September 30, 2021, results of operations, comprehensive (loss)/income and changes in stockholders' equity for the three and nine months ended September 30, 2021 and 2020, and cash flows for the nine months ended September 30, 2021 and 2020. The results of operations for the three and nine months ended September 30, 2021, are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. The consolidated balance sheet as of December 31, 2020 was derived from our audited consolidated financial statements. The COVID-19 pandemic has resulted in a global slowdown of economic activity. While the impact of the COVID-19 pandemic to our business and operating results presents additional uncertainty, we continue to use reasonably available information to assess certain accounting matters including, but not limited to, accounts receivable, inventory and the carrying value of goodwill and other long-lived tangible and intangible assets. While the assessments have not resulted in any material impacts to our financial statements as of September 30, 2021, we believe the full impact of the pandemic remains uncertain and ongoing developments related to the pandemic may cause material impacts to our consolidated financial statements. The consolidated interim financial statements, including our significant accounting policies, should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2020, included in our Annual Report on Form 10-K as filed with the Securities and Exchange Commission (“SEC”) on March 12, 2021.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill and intangible assets with indefinite lives are not amortized but are tested for impairment on an annual basis, as of October 1 of each year, or whenever events or changes in circumstances indicate that the carrying amount of these assets may not be recoverable. Purchased intangible assets with finite useful lives are amortized using the straight-line method over their estimated useful lives and reviewed for impairment as described above.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between marketplace participants. Various valuation approaches can be used to determine fair value, each requiring different valuation inputs. The following hierarchy classifies the inputs used to determine fair value into three levels: •Level 1—Quoted prices for identical instruments in active markets. •Level 2—Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which significant value drivers are observable. •Level 3—Valuations derived from valuation techniques in which significant value drivers are unobservable. The carrying values of cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximate fair value because of the short-term nature of these instruments. The carrying amount of lease liabilities approximate fair value because these financial instruments bear interest at rates that approximate current market rates for similar agreements with similar maturities and credit. We consider the terms of the PNC Bank, National Association debt facility including its interest rate of LIBOR plus a margin ranging from 1.75% to 2.25%, to be at market based upon similar instruments that would be available to us.
Reportable Segments	Reportable Segments During the three months ended September 30, 2021, we classified one of our reporting segments, Luna Labs, as held for sale. Therefore, we will only have one reportable segment remaining. See Note 2 for additional disclosure related to discontinued operations and assets held for sale. The remaining segment, Lightwave, develops, manufactures and markets distributed fiber optic sensing products and fiber optic communications test and control products. The segment now held for sale, Luna Labs, performs applied research principally in the areas of sensing and instrumentation, advanced materials and health sciences.
Net Income Per Share	Net Income Per ShareBasic per share data is computed by dividing our net income by the weighted average number of shares outstanding during the period. Diluted per share data is computed by dividing net income by the weighted average shares outstanding during the period increased to include, if dilutive, the number of additional common share equivalents that would have been outstanding if potential shares of common stock had been issued using the treasury stock method. Diluted per share data would also include the potential common share equivalents relating to convertible securities by application of the if-converted method.
Foreign Currency	Foreign CurrencyFor our non-U.S. dollar functional currency subsidiaries, assets and liabilities are translated into U.S. dollars using fiscal period end exchange rates. Sales and expenses are translated at average monthly exchange rates. Foreign currency translation gains and losses are included as a component of accumulated other comprehensive loss within equity. Gains and losses resulting from foreign currency transactions are included in earnings.
Recently Adopted Accounting Pronouncements/Recently Issued Pronouncements, net yet adopted	Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU 2019-12 Simplifying the Accounting for Income Taxes, which removes certain exceptions to the general principles of the accounting for income taxes and also improves consistent application of and simplification of other areas when accounting for income taxes. The guidance is effective for us beginning in the first quarter of fiscal year 2021. We adopted ASU 2019-12, effective January 1, 2021. The adoption of ASU 2019-12 did not have a significant impact on our consolidated financial statements. Recently Issued Pronouncements, Not Yet Adopted In June 2016, the FASB issued ASU 2016-13 Financial Instruments - Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments, which requires companies to measure financial assets at an amortized cost basis to be presented at the net amount expected to be collected. The new accounting rules eliminate the probable initial recognition threshold and, instead, reflect an entity's current estimate of all expected credit losses. ASU 2016-13 is applicable to our trade receivables. This pronouncement was amended under ASU 2019-10 to allow an extension on the adoption date for entities that qualify as a small reporting company. We have elected this extension and the effective date for us to adopt this standard will be for fiscal years beginning after December 15, 2022. We are currently in the process of evaluating the impact of ASU 2016-13, but we do not expect the adoption of this new accounting rule to have a significant impact on our consolidated financial statements.

Basis of Presentation and Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2021

Luna Innovations Incorporated (“we,” “Luna Innovations” or the “Company”), headquartered in Roanoke, Virginia, was incorporated in the Commonwealth of Virginia in 1990 and reincorporated in the State of Delaware in April 2003.

We are a leader in advanced optical technology, providing high performance fiber optic test, measurement and control products for the telecommunications and photonics industries, and distributed fiber optic sensing solutions that measure, or "sense" the structures for industries ranging from aerospace, automotive, oil and gas, security and infrastructure. Our communications test and control products help customers test their fiber optic networks and assemblies with speed and precision in both lab and production environments, accelerating the development of fiber optic products and assuring accurate testing of optical components like photonic integrated circuits ("PICs") and coherent receivers, which are both critical elements of meeting the world’s exponentially growing demand for bandwidth. Our distributed fiber optic sensing products help designers and manufacturers more efficiently develop new and innovative products by measuring stress, strain, and temperature at a high resolution for new designs or manufacturing processes. In addition, our distributed fiber optic sensing products ensure the safety and structural integrity or operational health of critical assets in the field, by monitoring stress, strain, and vibration in large civil and industrial infrastructure such as bridges, roads, pipelines and borders.

We also provide applied research services, typically under research programs funded by the U.S. government, in areas of advanced materials, sensing, and healthcare applications. Our business model is designed to accelerate the process of bringing new and innovative products to market. We use our in-house technical expertise across a range of technologies to perform applied research services for companies and for government funded projects. We continue to invest in product development and commercialization, which we anticipate will lead to increased product sales growth.

Unaudited Interim Financial Information

The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial statements and Article 10 of Regulation S-X of the Securities Exchange Act of 1934, as amended. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for annual financial statements. The unaudited consolidated interim financial statements have been prepared on the same basis as the annual financial statements and in the opinion of management reflect all adjustments, consisting of only normal recurring accruals considered necessary to present fairly our financial position at September 30, 2021, results of operations, comprehensive (loss)/income and changes in stockholders' equity for the three and nine months ended September 30, 2021 and 2020, and cash flows for the nine months ended September 30, 2021 and 2020. The results of operations for the three and nine months ended September 30, 2021, are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. The consolidated balance sheet as of December 31, 2020 was derived from our audited consolidated financial statements.

The COVID-19 pandemic has resulted in a global slowdown of economic activity. While the impact of the COVID-19 pandemic to our business and operating results presents additional uncertainty, we continue to use reasonably available information to assess certain accounting matters including, but not limited to, accounts receivable, inventory and the carrying value of goodwill and other long-lived tangible and intangible assets. While the assessments have not resulted in any material impacts to our financial statements as of September 30, 2021, we believe the full impact of the pandemic remains uncertain and ongoing developments related to the pandemic may cause material impacts to our consolidated financial statements.

The consolidated interim financial statements, including our significant accounting policies, should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2020, included in our Annual Report on Form 10-K as filed with the Securities and Exchange Commission (“SEC”) on March 12, 2021.

Goodwill and Intangible Assets

Goodwill and intangible assets with indefinite lives are not amortized but are tested for impairment on an annual basis, as of October 1 of each year, or whenever events or changes in circumstances indicate that the carrying amount of these assets

may not be recoverable. Purchased intangible assets with finite useful lives are amortized using the straight-line method over their estimated useful lives and reviewed for impairment as described above.

Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between marketplace participants. Various valuation approaches can be used to determine fair value, each requiring different valuation inputs. The following hierarchy classifies the inputs used to determine fair value into three levels:

•Level 1—Quoted prices for identical instruments in active markets.

•Level 2—Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which significant value drivers are observable.

•Level 3—Valuations derived from valuation techniques in which significant value drivers are unobservable.

The carrying values of cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximate fair value because of the short-term nature of these instruments. The carrying amount of lease liabilities approximate fair value because these financial instruments bear interest at rates that approximate current market rates for similar agreements with similar maturities and credit. We consider the terms of the PNC Bank, National Association debt facility including its interest rate of LIBOR plus a margin ranging from 1.75% to 2.25%, to be at market based upon similar instruments that would be available to us.

Reportable Segments

During the three months ended September 30, 2021, we classified one of our reporting segments, Luna Labs, as held for sale. Therefore, we will only have one reportable segment remaining. See Note 2 for additional disclosure related to discontinued operations and assets held for sale.

The remaining segment, Lightwave, develops, manufactures and markets distributed fiber optic sensing products and fiber optic communications test and control products. The segment now held for sale, Luna Labs, performs applied research principally in the areas of sensing and instrumentation, advanced materials and health sciences.

Net Income Per Share

Net Income Per ShareBasic per share data is computed by dividing our net income by the weighted average number of shares outstanding during the period. Diluted per share data is computed by dividing net income by the weighted average shares outstanding during the period increased to include, if dilutive, the number of additional common share equivalents that would have been outstanding if potential shares of common stock had been issued using the treasury stock method. Diluted per share data would also include the potential common share equivalents relating to convertible securities by application of the if-converted method.

Foreign Currency

Foreign CurrencyFor our non-U.S. dollar functional currency subsidiaries, assets and liabilities are translated into U.S. dollars using fiscal period end exchange rates. Sales and expenses are translated at average monthly exchange rates. Foreign currency translation gains and losses are included as a component of accumulated other comprehensive loss within equity. Gains and losses resulting from foreign currency transactions are included in earnings.

Recently Adopted Accounting Pronouncements/Recently Issued Pronouncements, net yet adopted

Recently Adopted Accounting Pronouncements

In December 2019, the FASB issued ASU 2019-12 Simplifying the Accounting for Income Taxes, which removes certain exceptions to the general principles of the accounting for income taxes and also improves consistent application of and simplification of other areas when accounting for income taxes. The guidance is effective for us beginning in the first quarter of fiscal year 2021. We adopted ASU 2019-12, effective January 1, 2021. The adoption of ASU 2019-12 did not have a significant impact on our consolidated financial statements.

Recently Issued Pronouncements, Not Yet Adopted

In June 2016, the FASB issued ASU 2016-13 Financial Instruments - Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments, which requires companies to measure financial assets at an amortized cost basis to be presented at the net amount expected to be collected. The new accounting rules eliminate the probable initial recognition threshold and, instead, reflect an entity's current estimate of all expected credit losses. ASU 2016-13 is applicable to our trade receivables. This pronouncement was amended under ASU 2019-10 to allow an extension on the adoption date for entities that qualify as a small reporting company. We have elected this extension and the effective date for us to adopt this standard will be for fiscal years beginning after December 15, 2022. We are currently in the process of evaluating the impact of ASU 2016-13, but we do not expect the adoption of this new accounting rule to have a significant impact on our consolidated financial statements.