Commitments and Contingencies Future minimum lease payments (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Operating leases:
2017	$ 2,910
2018	2,590
2019	2,464
2020	2,451
2021	2,255
Thereafter	1,202
Liability	13,872
Financing lease:
2017	1,348
2018	1,395
2019	1,444
2020	1,493
2021	542
Thereafter	0
Total	6,222
Capital leases:
2017	169
2018	112
2019	72
2020	36
2021	0
Thereafter	0
Total	$ 389

Amount of minimum lease payments for capital leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 40
-Section 50
-Paragraph 2
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 20
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-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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