8. Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax liabilities:
Net deferred tax assets	$ 6,033
Current
Deferred tax assets:
Operating loss carryforwards	2,009	1,542
R and D tax credit	0	0
AMT tax credit	0	0
Section 263A costs	421	535
Research and development costs	170	219
Amortization	0	0
Asset reserves:
Bad debts	18	30
Inventory reserve	608	1,058
Accrued expenses:
Non-qualified stock options	0	0
Compensation	202	199
Warranty	315	253
Deferred tax assets	3,743	3,836
Less valuation allowance	0	0
Less APIC pool reserve	0	0
Total deferred tax assets	3,743	3,836
Deferred tax liabilities:
Depreciation	0	0
Amortization	0	0
Total deferred tax liabilities	0	0
Net deferred tax assets	3,743	3,836
Long Term
Deferred tax assets:
Operating loss carryforwards	778	1,651
R and D tax credit	1,021	951
AMT tax credit	269	266
Section 263A costs	0
Research and development costs	1,258	1,209
Amortization	0	0
Asset reserves:
Bad debts	0	0
Inventory reserve	0	0
Accrued expenses:
Non-qualified stock options	78	78
Compensation	0	0
Warranty	0	0
Deferred tax assets	3,404	4,155
Less valuation allowance	0	0
Less APIC pool reserve	(380)	(380)
Total deferred tax assets	3,024	3,775
Deferred tax liabilities:
Depreciation	(370)	(507)
Amortization	(364)	(196)
Total deferred tax liabilities	(734)	(703)
Net deferred tax assets	$ 2,290	$ 3,072