Retirement savings plan - Note 13	12 Months Ended
Dec. 31, 2017
Notes to Financial Statements
Retirement savings plan - Note 13	13. RETIREMENT SAVINGS PLAN We have a retirement savings plan that qualifies under Internal Revenue Code Section 401(k). The plan covers all qualified employees. Contributions to the plan are made at the discretion of our Board of Directors. During the years ended December 31, 2017, 2016, and 2015 we contributed $278,000, $214,000, and $108,000 to the plan, respectively.

The entire disclosure for postemployment benefits, which may include supplemental unemployment benefits, obligations recognized for all types of benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement. Disclosure may also include discussion that an obligation for postemployment benefits is not accrued in accordance with regulation only because the amount cannot be reasonably estimated.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 712
-URI http://asc.fasb.org/topic&trid=2197446

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