As of December 31, 2019, 2018 and 2017, current restricted cash amounted to $3,000, $3,000, and $0, respectively. The restricted cash was held as pledges for letters of credit issued to support our operations. See the table below for reconciliation of Cash and cash equivalents and restricted cash in regard to the Consolidated Statements of Cash Flows:

The Company's marketable securities are classified as available-for-sale and are reported at fair value, with unrealized gains and losses, net of tax, recorded in "Accumulated other comprehensive income (loss)". Realized gains or losses and declines in value judged to be other-than-temporary, if any, on available-for-sale securities are reported in "Other income (expense), net". The Company evaluates such investments periodically for possible other-than-temporary impairment. A decline of fair value below amortized costs of debt securities is considered an other-than-temporary impairment if the Company has the intent to sell the security or if it is more likely than not that the Company will be required to sell the security before recovery of the entire amortized cost basis. In those instances, an impairment charge equal to the difference between the fair value and the amortized cost basis is recognized in earnings. Regardless of the Company's intent or requirement to sell a debt security, an impairment is considered other-than-temporary if the Company does not expect to recover the entire amortized cost basis; in those instances, a credit loss equal to the difference between the present value of the cash flows expected to be collected based on credit risk and the amortized cost basis of the debt security is recognized in earnings. The Company has no marketable securities as of December 31, 2019.

Accounts receivable are carried at invoiced amount less allowance for doubtful accounts. Management estimates the allowance for doubtful accounts based on existing economic conditions, the financial conditions of customers and the amount and age of past due accounts. Receivables are considered past due if full payment is not received by the contractual due date. Past due accounts are generally written off against the allowance for doubtful accounts only after reasonable collection attempts have been exhausted.

When the Company produces and sells a gallon of biomass-based diesel, 1.5 to 1.7 RINs per gallon are generated. RINs are used to track compliance with the RFS2. RFS2 allows the Company to attach between zero and 2.5 RINs to a gallon of biomass-based diesel. As a result, a portion of the selling price for a gallon of biomass-based diesel is generally attributable to RFS2 compliance. However, RINs that the Company generates are a form of government incentive and not a result of the physical attributes of the biomass-based diesel production. Therefore, no cost is allocated to the RIN when it is generated, regardless of whether the RIN is transferred with the biomass-based diesel produced or held by the Company pending attachment to other biomass-based diesel.

In addition, the Company also obtains RINs from third parties who have separated the RINs from gallons of biomass-based diesel. From time to time, the Company holds varying amounts of these separated RINs for resale. RINs obtained from third parties are initially recorded at their cost and are subsequently revalued at the lower of cost or net realizable as of the last day of each accounting period. The resulting adjustments are reflected in costs of goods sold for the period. The value of these RINs is reflected in “Prepaid expenses and other assets” on the Consolidated Balance Sheets. The cost of goods sold related to the sale of these RINs is determined using the average cost method, while market prices are determined by RIN values, as reported by OPIS.

The Company generates Low Carbon Fuel Standard ("LCFS") credits for its low carbon fuels or blendstocks when its qualified low carbon fuels are transported into an LCFS market. LCFS credits are used to track compliance with LCFS. As a result, a portion of the selling price for a gallon of biomass-based diesel sold into an LCFS market is also attributable to LCFS compliance. However, LCFS credits that the Company generates are a form of government incentive and not a result of the physical attributes of the biomass-based diesel production. Therefore, no cost is allocated to the LCFS credit when it is generated, regardless of whether the LCFS credit is transferred with the biomass-based diesel produced or held by the Company.

In addition, the Company also obtains LCFS credits from third party trading activities. From time to time, the Company holds varying amounts of these third party LCFS credits for resale. LCFS credits obtained from third parties are initially recorded at their cost and are subsequently revalued at the lower of cost or net realizable value as of the last day of each accounting period and the resulting adjustments are reflected in costs of goods sold for the period. The value of LCFS credits obtained from third parties is reflected in “Prepaid expenses and other assets” on the Consolidated Balance Sheets. The cost of goods sold related to the sale of these LCFS credits is determined using the average cost method, while market prices are determined by LCFS values, as reported by the OPIS. At December 31, 2019 and 2018, the Company held no LCFS credits purchased from third parties.

In June 2017, the Company experienced a fire at its Madison facility, resulting in the shutdown of the facility. In 2017, the Company impaired fixed assets with a total net book value of approximately $2,671 as a result of the fire in June 2017. The Company received payments in the amounts of $12,454 and $9,484 to cover initial costs incurred for property losses and business interruption, respectively. The Company recognized a final business interruption gain related to the fire of $4,454 for the year ended December 31, 2018.

Goodwill is tested for impairment annually on July 31 or when impairment indicators exist. Goodwill is allocated and tested for impairment by reporting units. At December 31, 2019 and 2018, the Company had goodwill in the Services reporting unit. The annual impairment test at July 31, 2019 determined that the fair value of the Services reporting unit exceeded its carrying value by approximately 5%. No impairment of goodwill was recorded during the years ended December 31, 2019 and 2018.

The Company tests its long-lived assets for recoverability when events or circumstances indicate that its carrying amount may not be recoverable. Significant assumptions used in the undiscounted cash flow analysis, when it is required, include the projected demand for biomass-based diesel based on annual renewable fuel volume obligations under the RFS2, the Company's capacity to meet that demand, the market price of biomass-based diesel and the cost of feedstock used in the manufacturing process. For facilities under construction, estimates also include the capital expenditures necessary to complete construction of the plant and the projected costs of financing.

During 2019, the Company recorded impairment charges of $12,208, of which $11,145 was related to its New Boston facility's property, plant and equipment resulting from the closing of the plant and the unlikelihood that the plant will be reopened in the near future due to the deteriorating economic conditions uniquely facing the plant. The impairment charge reflected the difference between the carrying amount and the estimated fair value. The fair value was determined based on a cost approach. The inputs include replacement cost estimates adjusted for physical deterioration and economic obsolescence. This method of assigning fair value to each asset type and aggregating those values represents a Level 3 asset measurement in determining the fair value on a nonrecurring basis subsequent to its original recognition. In 2018, impairment charges on continuing operations of $879 were recorded related to certain identified plant property, plant and equipment at our current facilities as the carrying amounts of those assets were deemed not recoverable. Refer to "Note 6 - Discontinued Operations" for details on asset impairments related to discontinued operations. In 2017, impairment charges of $44,649 and $5,224 were recorded related to the Company's New Orleans facility's property, plant and equipment assets and certain other plant, property and equipment.

In June 2014, the Company issued $143,800 aggregate principal amount of 2.75% of convertible senior notes due in 2019 (the "2019 Convertible Senior Notes"). During the year ended December 31, 2018, the Company used $6,689 under the 2017 Program (defined below in "Security Repurchase Programs") to repurchase $6,311 principal amount of the 2019 Convertible Senior Notes. On June 15, 2019, the 2019 Convertible Senior Notes matured. The Company elected to settle the principal balance with cash and the excess conversion amount was satisfied by the Company issuing 1,902,781 shares of treasury stock at settlement.

In June 2016, the Company issued $152,000 aggregate principal amount of 4% convertible senior notes due in 2036 (the "2036 Convertible Senior Notes"). See "Note 11 - Debt" for a further description of the 2036 Convertible Senior Notes. During the year ended December 31, 2019, the Company used $14,638, of which $9,402 was settled after year end, to repurchase $6,673 principal amount of the 2036 Convertible Senior Notes, reflecting conversion premium, after tax impact, of $9,715 as a reduction of Additional Paid-in Capital and gains on debt extinguishment of $488 in the Consolidated Statements of Operations. During the year ended December 31, 2018, the Company used $110,828 to repurchase $55,700 principal amount of the 2036 Convertible Senior Notes, reflecting conversion premium, after tax impact of $70,011 as a reduction of Additional Paid-in Capital and gains on debt extinguishment of $6,065 in the Consolidated Statements of Operations.

In connection with the issuance of the 2019 Convertible Senior Notes, the Company entered into capped call transactions. The purchased capped call transactions were recorded as a reduction to common stock-additional paid-in-capital. During 2016, in connection with the issuance of the 2036 Convertible Senior Notes, certain call options covered by the original capped call transaction were rebalanced and reset to cover 100% of the total number of shares of the Company's Common Stock underlying the remaining principal of the 2019 Convertible Senior Notes. As part of the settlement of the 2019 Convertible Senior Notes, the Company settled all related capped call options in June 2019 and received 625,558 shares of common stock. The impact of these transactions, net of tax, was reflected as an addition/reduction to "Common Stock-Additional Paid-In Capital" as presented in the Consolidated Statements of Stockholders' Equity.

In December 2017, June 2018 and January 2019, the Company's Board of Directors approved a repurchase program, each of up to $75,000 of the Company's convertible notes and/or shares of common stock (the "2017 Program", "2018 Program", and "2019 Program", respectively). Under these programs, the Company may repurchase convertible notes or shares from time to time in open market transactions, privately negotiated transactions or by other means. The timing and amount of repurchase transactions under each program are determined by the Company's management based on its evaluation of market conditions, share price, bond price, legal requirements and other factors. The table below sets out the information regarding the activities under the 2017 Program, the 2018 Program and 2019 Program during 2018 and 2019:



	For the year ended December 31, 2019								For the year ended December 31, 2018
	Number of shares/Principal amount in $'000		June 2018 Program		January 2019 Program		Both Programs		Number of shares/Principal amount in $'000		December 2017 Program		June 2018 Program		Both Programs
Repurchases of shares of common stock	—		$	—	$	—	$	—	1,937,844		$	25,048	$	—	$	25,048
2019 Convertible Senior Notes Repurchases	$	—	$	—	$	—	$	—	$	6,311	$	6,689	$	—	$	6,689
2036 Convertible Senior Notes Repurchases	$	6,673	$	7,435	$	7,203	$	14,638	$	55,700	$	43,263	$	67,565	$	110,828

The Company’s reporting and functional currency is U.S. dollars. Monetary assets and liabilities denominated in currencies other than U.S. dollars are remeasured into their respective functional currencies at exchange rates in effect at the balance sheet date. The resulting exchange gain or loss is included in the Company’s Consolidated Statements of Operations as foreign exchange gain (loss) unless the remeasurement gain or loss relates to an intercompany transaction that is of a long-term investment nature and for which settlement is not planned or anticipated in the foreseeable future. Gains or losses arising from translation of such transactions are reported as a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets.

The Company translates the assets and liabilities of its foreign subsidiaries from their respective functional currencies to U.S. dollars at the appropriate spot rates as of the balance sheet date. Generally, the Company's foreign subsidiaries use the local currency as their functional currency. Changes in the carrying value of these assets and liabilities attributable to fluctuations in spot rates are recognized in foreign currency translation adjustment, a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets.

The other comprehensive loss amounts presented in the Company's Consolidated Statements of Comprehensive Income (Loss) and Consolidated Statements of Stockholders' Equity mainly include the foreign currency translation adjustment resulting from translating the financial statements of certain subsidiaries from Euros to US Dollars, the Company's functional currency.

The Company generally has a single performance obligation in its arrangements with customers. The Company believes for most of its contracts with customers, control is transferred at a point in time, typically upon delivery to the customers. When the Company performs shipping and handling activities after the transfer of control to the customers (e.g., when control transfers prior to delivery), they are considered as fulfillment activities, and accordingly, the costs are accrued for when the related revenue is recognized. Taxes collected from customers relating to product sales and remitted to governmental authorities are excluded from revenues. The Company generally expenses sales commissions when incurred because the amortization period would have been less than one year. The Company records these costs within selling, general and administrative expenses.



	Reportable Segments
Year ended December 31, 2019	Biomass-based Diesel		Services		Corporate and other		Intersegment Revenues			Consolidated Total
Biomass-based diesel sales, net of BTC related amount due to customers of $157,896	$	1,400,973	$	—	$	—	$	(11,309	)	$	1,389,664
Petroleum and blended petroleum diesel sales	—		—		270,326		—			270,326
Other biomass-based diesel revenue	215,086		—		—		—			215,086
Separated RIN sales	98,285		—		—		—			98,285
Other revenues	—		99,086		—		(97,446		)	1,640
Total revenues from contracts with customers	$	1,714,344	$	99,086	$	270,326	$	(108,755	)	$	1,975,001
Biomass-based diesel government incentives	666,392		—		—		—			666,392
Total revenues	$	2,380,736	$	99,086	$	270,326	$	(108,755	)	$	2,641,393



	Reportable Segments
Year ended December 31, 2018	Biomass-based Diesel		Services		Corporate and other		Intersegment Revenues			Consolidated Total
Biomass-based diesel sales, net of BTC related amount due to customers of $144,944	$	1,474,459	$	—	$	9,682	$	(26,348	)	$	1,457,793
Petroleum and blended petroleum diesel sales	—		—		239,470		—			239,470
Other biomass-based diesel revenue	178,053		—		—		—			178,053
Separated RIN sales	137,895		—		—		—			137,895
Other revenues	—		93,347		—		(91,061		)	2,286
Total revenues from contracts with customers	$	1,790,407	$	93,347	$	249,152	$	(117,409	)	$	2,015,497
Biomass-based diesel government incentives	367,490		—		—		—			367,490
Total revenues	$	2,157,897	$	93,347	$	249,152	$	(117,409	)	$	2,382,987

performance under the contract, and are realized with the associated revenue recognized under the contract. While in general the Company has not historically offered sales incentives to customers, the uncertainty around the reinstatement of the federal biodiesel tax credit led to the Company and other market participants acting as if the federal biodiesel tax credit would be reinstated throughout the year and entering into agreements with both customers and vendors throughout the year to capture the credit when, or if, reinstated. Due to the federal biodiesel tax credit reinstatement, the impacts of the agreements with customers are recorded as contract liabilities in accounts payable and as adjustments to Biomass-based diesel sales, whereas agreements with vendors are recorded net as adjustments to Biomass-based diesel costs of goods sold on the Consolidated Statements of Operations.

The Company sponsors an employee savings plan under Section 401(k) of the Internal Revenue Code. The Company makes matching contributions equal to 50% of the participant’s pre-tax contribution up to a maximum of 6% of the participant’s eligible earnings. Total expense related to the Company’s defined contribution plan was $1,815, $1,588 and $1,367 for the years ended December 31, 2019, 2018 and 2017, respectively.

The Company’s income tax provision, deferred income tax assets and liabilities, and liabilities for unrecognized tax benefits represent the Company’s best estimate of current and future income taxes to be paid. The annual effective tax rate is based on income tax laws, statutory tax rates, taxable income levels and tax planning opportunities available in various jurisdictions where the Company operates. These tax laws are complex and require significant judgment to determine the consolidated provision for income taxes. Changes in tax laws, statutory tax rates and estimates of the Company’s future taxable income levels could result in actual realization of deferred taxes being materially different from amounts provided for in the consolidated financial statements.

Income (loss) from discontinued operations was mainly related to the research and development activities of REG Life Sciences, the Company's industrial biotechnology business, which had been classified as assets held for sale following the Company's decision to pursue a sale of this business in the fourth quarter of 2018. In May 2019, the sale of REG Life Sciences core assets and business was closed. During the year ended December 31, 2019, the Company continued to incur costs that primarily relate to certain pre-existing contractual agreements and legal and professional fees related to the disposition and wind-down of operations. See "Note 6 - Discontinued Operations" for further details.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the dates of the financial statements and reported amounts of revenues and expenses during the reporting periods. These estimates are based on information that is currently available to management and on various assumptions that the Company believes to be reasonable under the circumstances. Actual results could differ from those estimates.

On February 25, 2016, the FASB issued ASU 2016-02, which introduces a lessee model that brings most leases on the balance sheet. The new standard also aligns many of the underlying principles of the new lessor model with those in ASC 606, the FASB’s new revenue recognition standard (e.g., those related to evaluating when profit can be recognized). Furthermore, the ASU addresses other concerns related to the current leases model.

On July 19, 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, Leases, which addresses certain aspects of the new leases standard, including the rate implicit in the lease, impairment of the net investment in the lease, lessee reassessment of lease classification, lessor reassessment of lease term and purchase options, variable payments that depend on an index or rate and certain transition adjustments, among other things. On July 31, 2018, the FASB issued ASU 2018-11, Codification Improvements to Topic 842, Leases, which provides entities with an additional (and optional) transition method to adopt the new leases standard. Under this new transition method, an entity initially applies the new leases standard at the adoption date and recognizes a cumulative effect adjustment to the opening balance of retained earnings in the period of adoption.

The Company adopted all of the ASU's related to ASC 842 effective January 1, 2019. The Company applied a modified retrospective transition approach. The Company did not elect the practical expedient (1) to reassess the lease classification for any expired or existing leases; (2) to reassess whether any expired or existing contracts are or contain leases and (3) to reassess initial direct costs. The Company elected the hindsight practical expedient to determine the reasonably certain lease term for existing leases and to assess the impairment of its right-of-use assets. While lease classification remained unchanged, hindsight resulted in generally shorter accounting lease terms and useful lives of the corresponding right of use assets. The hindsight analysis also resulted in an approximate negative impact on beginning retained earnings of $6,516, related to the impairment of a right of use asset at the company's New Orleans facility. The Company elected the transitional practical expedient for existing or expired land easements, allowing the Company to elect not to assess whether those land easements are, or contain, leases in accordance with ASC 842. The Company also elected the practical expedient to adjust the carrying amount of the right-of-use assets for the unfavorable lease liability previously recognized on the balance sheet. Additionally, the Company made an accounting policy election that keeps leases with an initial term of 12 months or less off of the balance sheet and resulted in recognizing those lease payments in the Consolidated Statements of Operations on a straight-line basis over the lease term. Refer to "Note 14 -Leases" for further detail.

On August 28, 2017, the FASB issued ASU 2017-12, which amends the hedge accounting recognition and presentation requirements in ASC 815 to (1) improve the transparency and understandability of information conveyed to financial statement users about an entity's risk management activities by better aligning the entity's financial reporting for hedging relationships with

those risk management activities and (2) reduce the complexity of and simplify the application of hedge accounting by preparers. For public business entities, the amendments in this Update are effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. The Company believes that the ASU 2017-12 will allow more of its derivative contracts to qualify for hedge accounting elections. The Company adopted ASU 2017-12 effective January 1, 2019 and changes in fair value of derivatives continue to be recognized in current period earnings.

On November 7, 2018, the FASB issued ASU 2018-16, which permits entities to use the Overnight Index Swap ("OIS") Rate based on Secured Overnight Financing Rate ("SOFR") as an eligible benchmark interest rate during the early stages of the transition from LIBOR to SOFR. For public business entities, the amendments in ASU 2018-16 are effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. The Company's adoption of ASU 2018-16 did not have a material impact on its consolidated financial statements.

On June 16, 2016, the FASB issued ASU 2016-13, which amends the Board’s guidance on the impairment of financial instruments. The ASU adds to U.S. GAAP an impairment model (known as the current expected credit loss (CECL) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. For public companies, the ASU is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company has evaluated the impact of this guidance, and the adoption will not have a material impact on its consolidated financial statements.

On August 28, 2018, the FASB issued ASU 2018-13, which changes the fair value measurement disclosure requirements of ASC 820. ASU 2018-13 eliminates or modifies certain disclosure requirements of ASC 820 and requires new disclosures relating to changes in unrealized gains or losses included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the applicable reporting period. ASU 2018-13 also explicitly requires entities to disclose the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. ASU 2018-13 is effective for all entities for fiscal years beginning after December 15, 2019, including interim periods therein. The Company has evaluated the impact of this guidance on its consolidated financial statements and the adoption will not have a material impact on its consolidated financial statements.

On December 18, 2019, the FASB issued ASU 2019-12, which affects general principles within ASC 740, Income Taxes. The ASU removes the following exceptions: (1) incremental approach for intra-period tax allocation when there is a loss from continuing operations and income or a gain from other items, (2) exception to the requirement to recognize a deferred tax liability for equity method investments when a foreign subsidiary becomes an equity method investment, (3) exception to the ability not to recognize a deferred tax liability for a foreign subsidiary when a foreign equity method investment becomes a subsidiary, and (4) exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. The ASU also will make changes to franchise tax recognition, consideration of the tax basis recognition of goodwill related to acquisitions, specify tax allocation to subsidiaries, reflecting a change in tax law in the interim period annual effective tax rate computation in the period of enactment, and changes to the employee stock ownership plans and investments. For public business entities, the amendments in ASU 2019-12 are effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company is evaluating the impact of the guidance on its consolidated financial statements, but does not expect the impact to be significant.