10. Employee Retirement and Benefit Plans	12 Months Ended
Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Retirement and Benefit Plans	We sponsor a defined contribution 401(k) plan for all employees. Each participant may contribute certain amounts of eligible compensation. We make a matching contribution to the plan. Our contributions under this plan were $667,000, $645,000 and $600,000 in 2016, 2015 and 2014, respectively.

The entire disclosure for pension and other postretirement benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
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