Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (5,208)	$ (25,940)
Adjustments to reconcile net loss to cash provided by operating activities:
Depreciation	3,234	4,185
Amortization of intangible assets	2,862	2,932
Gain on insurance proceeds	(1,000)
Lower of cost or net realizable value inventory adjustment	(3,935)	(740)
Allowance for doubtful accounts	880	(76)
Amortization of deferred finance costs	1,127	2,791
Value of share-based payment arrangements	656	1,829
Write-off of intangible assets		507
Deferred tax expense	163	749
Non-cash adjustment of cylinder deposits		(502)
Changes in assets and liabilities:
Trade accounts receivable	(2,625)	6,080
Inventories	18,713	43,464
Prepaid and other assets	(2,192)	(579)
Lease obligations	12	58
Income taxes receivable/payable	(300)	108
Accounts payable and accrued expenses	(700)	(1,045)
Cash provided by operating activities	11,687	33,821
Cash flows from investing activities:
Additions to property, plant, and equipment	(1,470)	(1,011)
Proceeds from Insurance Policy	1,000
Cash used in investing activities	(470)	(1,011)
Cash flows from financing activities:
Net proceeds from issuances of common stock and exercises of stock options	63	9
Borrowing - Paycheck Protection Program	2,475
Payment of deferred financing costs		(1,346)
Repayment of short-term debt	(12,000)	(15,000)
Repayment of long-term debt	(3,007)	(16,145)
Cash used in financing activities	(12,469)	(32,482)
(Decrease) increase in cash and cash equivalents	(1,252)	328
Cash and cash equivalents at beginning of period	2,600	2,272
Cash and cash equivalents at end of period	1,348	2,600
Supplemental Disclosure of Cash Flow Information:
Cash paid during period for interest	11,380	15,162
Refund received for income taxes - net	$ (48)	$ (202)