Revenue Recognition  On January 1, 2018, the Company adopted Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) No. 606, Revenue from Contracts with Customers, utilizing the modified retrospective method applied to contracts that were not completed. The adoption of the standard did not have a material impact on the timing and amounts of the Companys revenue, processes or internal controls. Upon adoption, the Company did not have any material remaining performance obligations, significant judgements, or material costs to obtain or fulfill contracts with its customers.  The Company enters into contracts to sell and distribute products and services to hospitals and surgical facilities for use in caring for patients with peripheral nerve damage or transection. Revenue is recognized when the Company has met its performance obligations pursuant to its contracts with its customers in an amount that the Company expects to be entitled to in exchange for the transfer of control of the products and services to the Companys customers.  In the case of products or services sold to a customer under a distribution or purchase agreement, the customers are granted exclusive distribution rights to sell the implants internationally in a territory defined by the contract. These international distributor agreements contain provisions that allow the Company to terminate the distribution agreement with the distributor, and upon termination, the right to repurchase inventory from the distributor at the distributors cost. The Company has determined that its contractual rights to repurchase distributor inventory upon termination of the distributor agreement are not substantive and do not impact the timing of when control transfers; and, therefore, the Company has determined it is appropriate to recognize revenue when: i) the product is shipped via common carrier; or ii) the product is delivered to the customer or distributor, depending on the terms of the agreement. Determining the timing of revenue recognition for such contracts is subject to significant judgment, because an evaluation must be made regarding the distributors ability to direct the use of, and obtain substantially all of the remaining benefits from, the implants received from the Company. Changes in these assessments could have a significant impact on the timing of revenue recognition from sales to distributors.  A portion of the Company's product revenue is generated from consigned inventory maintained at hospitals and independent sales agencies, and also from inventory physically held by field sales representatives. For these types of products sales, the Company retains control until the product has been used or implanted, at which time revenue is recognized.  The Company elected to account for shipping and handling activities as a fulfillment cost rather than a separate performance obligation. Amounts billed to customers for shipping and handling are included as part of the transaction price and recognized as revenue when control of the underlying products is transferred to the customer. The related shipping and freight charges incurred by the Company are included in cost of sales.  The Company operates in a single reportable segment of peripheral nerve repair, offers similar products to its customers, and enters into consistently structured arrangements with similar types of customers. As such, the Company does not disaggregate revenue from contracts with customers as the nature, amount, timing and uncertainty of revenue and cash flows does not materially differ within and among the contracts with customers.  The contract with the customer states the final terms of the sale, including the description, quantity, and price of each implant distributed. The payment terms and conditions in the Companys contracts vary; however, as a common business practice, payment terms are typically due in full within 30 to 60 days of delivery. Since the customer agrees to a stated price in the contract that does not vary over the contract term, the contracts do not contain any material types of variable consideration, and contractual rights of return are not material. The Company has several contracts with distributors in international markets which include consideration paid to the customer in exchange for distinct marketing and other services. The Company records such consideration paid to the customer as a reduction to revenue from the contracts with those distributor customers.  In connection with the Acroval Neurosensory and Motor Testing System, the Company sold extended warranty and service packages to some of its customers who purchase this evaluation and measurement tool, and the prepayment of these extended warranties represent contract liabilities until the performance obligations are satisfied ratably over the term of the contract. The sale of the aforementioned extended warranty represents the only performance obligation the Company satisfies over time and creates the contract liability disclosed below. The opening and closing balances of the Companys contract receivables and liabilities are as follows:            Contract Balances      Net Receivables  Contract Liabilities, Current  Contract Liabilities, Long-Term Opening, January 1, 2018  $ 11,065   32   69 Closing, December 31, 2018   15,321   18   42 Increase (decrease)   4,256   (14)   (27)           Opening, January 1, 2019  $ 15,321   18   42 Closing, December 31, 2019   16,944   14   15 Increase (decrease)   1,623   (4)   (27)