CONSOLIDATED BALANCE SHEETS - USD ($)	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 3,393,186	$ 4,594,007	$ 7,427,273
Accounts receivable, net	1,765,722	3,377,451	2,794,626
Inventory, net	10,979,891	11,208,658	9,770,206
Prepaid expenses and other assets	916,162	969,857	682,083
Total current assets	17,054,961	20,149,973	20,674,188
Long-term assets:
Inventory, net	20,848,647	19,764,959	18,360,211
Property and equipment, net	1,144,198	1,242,200	1,391,116
Intangible assets, net	34,833	8,597	8,808
Other assets	389,868	64,978	71,453
Total long-term assets	22,417,546	21,080,734	19,831,588
TOTAL ASSETS	39,472,507	41,230,707	40,505,776
Current liabilities:
Accounts payable	4,170,952	4,466,163	3,977,149
Accrued expenses and other liabilities	618,945	980,800	631,107
Total current liabilities	4,789,897	5,446,963	4,608,256
Long-term liabilities:
Deferred rent	393,051	463,526	594,916
Accrued income taxes	471,126	461,592	433,983
Total long-term liabilities	864,177	925,118	1,028,899
Total liabilities	5,654,074	6,372,081	5,637,155
Commitments and contingencies (Note 9)
Shareholders' equity:
Common stock, no par value; 50,000,000 shares authorized; 21,705,173, 21,580,102 and 21,369,885 shares issued and outstanding at June 30, 2018, December 31, 2017 and December 31, 2016, respectively	54,243,816	54,243,816	54,243,816
Additional paid-in capital	14,962,071	14,726,438	14,282,956
Accumulated deficit	(35,387,454)	(34,111,628)	(33,658,151)
Total shareholders' equity	33,818,433	34,858,626	34,868,621
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 39,472,507	$ 41,230,707	$ 40,505,776