Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 963	$ 840
Treasury bills	7,711	7,427
Available-for-sale securities	45	0
Trade receivables, less allowance for doubtful accounts of $11 and $8, respectively	902	770
Inventories	1,552	1,515
Other current assets	141	174
Income tax receivable	45	66
Total current assets	11,359	10,792
Deferred income tax asset	182	198
Intangible assets, net	800	1,035
Property and equipment, net	1,074	1,033
Total assets	13,415	13,058
Current liabilities
Contingent earn-out	150	0
Accounts payable	178	239
Accrued expenses	380	304
Total current liabilities	708	543
Long-term liabilities
Contingent earn-out	0	195
Total long-term liabilities	0	195
Commitments and contingencies
Stockholders' equity
Common stock par value $0.10 per share; authorized 10,000,000 shares; 3,395,521 shares issued and outstanding	339	339
Additional paid-in capital	2,004	1,953
Retained earnings	10,352	10,057
Accumulated other comprehensive gain (loss) (unrealized gain (loss) on available-for-sale securities, net of income tax)	12	(29)
Total stockholders' equity	12,707	12,320
Total liabilities and stockholders' equity	$ 13,415	$ 13,058

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.