Income Taxes	3 Months Ended
Mar. 31, 2018
Income taxes
Income Taxes	8.Income Taxes The federal Tax Cut and Jobs Act of 2017 (the “Tax Reform Act”) was enacted December 22, 2017. Effective January 1, 2018, the Tax Reform Act reduced statutory corporate income tax rates from 35% to 21% in addition to other tax changes including re-valuation of deferred tax assets and liabilities. For the first quarter of 2018, the Company realized an income tax benefit of $20,000, or an effective rate of 13.5%, which reflects the new federal corporate rate of 21% versus the income tax benefit of $223,000, or an effective rate of 37.0%, for the first quarter of 2017. The Company’s 2018 and 2017 first quarter tax benefit was due to the year to date net loss. The income tax provision for the 2018 and 2017 periods differ from the expected benefit due to credits for research and development, and other non-deductible items. The Company’s federal net operating loss carryforward and research and development credit carryover as of March 31, 2018 was $167,000 and $27,000, respectively, and will begin to expire in 2036. The Company’s state net operating loss carryforwards and research and development credit carryover as of March 31, 2018 was $834,000 and $91,000, respectively and begin to expire in 2026. The valuation allowance balance of $91,000 at March 31, 2018, relates entirely to Minnesota research and development credit carryforwards that the Company does not expect to utilize and begin to expire in 2028. It has been the Company’s policy to recognize interest and penalties related to uncertain tax positions in income tax expense. As of March 31, 2018 and December 31, 2017, there was no liability for unrecognized tax benefits. The Company is subject to federal and state taxation. As of March 31, 2018, with few exceptions, the Company is no longer subject to examination prior to tax year 2014.

8.Income Taxes

The federal Tax Cut and Jobs Act of 2017 (the “Tax Reform Act”) was enacted December 22, 2017. Effective January 1, 2018, the Tax Reform Act reduced statutory corporate income tax rates from 35% to 21% in addition to other tax changes including re-valuation of deferred tax assets and liabilities.

For the first quarter of 2018, the Company realized an income tax benefit of $20,000, or an effective rate of 13.5%, which reflects the new federal corporate rate of 21% versus the income tax benefit of $223,000, or an effective rate of 37.0%, for the first quarter of 2017. The Company’s 2018 and 2017 first quarter tax benefit was due to the year to date net loss. The income tax provision for the 2018 and 2017 periods differ from the expected benefit due to credits for research and development, and other non-deductible items.

The Company’s federal net operating loss carryforward and research and development credit carryover as of March 31, 2018 was $167,000 and $27,000, respectively, and will begin to expire in 2036. The Company’s state net operating loss carryforwards and research and development credit carryover as of March 31, 2018 was $834,000 and $91,000, respectively and begin to expire in 2026.

The valuation allowance balance of $91,000 at March 31, 2018, relates entirely to Minnesota research and development credit carryforwards that the Company does not expect to utilize and begin to expire in 2028.

It has been the Company’s policy to recognize interest and penalties related to uncertain tax positions in income tax expense. As of March 31, 2018 and December 31, 2017, there was no liability for unrecognized tax benefits.

The Company is subject to federal and state taxation. As of March 31, 2018, with few exceptions, the Company is no longer subject to examination prior to tax year 2014.