Line-of-Credit and Long-term Debt - Outstanding Indebtedness and Respective Principal Maturities (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Maturities of Long-term Debt [Abstract]
2018	$ 4,003
2019	4,059
2020	4,183
2021	4,366
2022	4,549
Thereafter	48,799
Total	69,959
Term loan
Maturities of Long-term Debt [Abstract]
2018	3,563
2019	3,715
2020	3,881
2021	4,051
2022	4,221
Thereafter	46,615
Total	66,046
Promissory note
Maturities of Long-term Debt [Abstract]
2018	277
2019	289
2020	302
2021	315
2022	328
Thereafter	2,184
Total	3,695
Other borrowings
Maturities of Long-term Debt [Abstract]
2018	163
2019	55
2020	0
2021	0
2022	0
Thereafter	0
Total	$ 218

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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