Debt - Maturities of Borrowings (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Summary of maturities of the term borrowings
2018	$ 13,397
2019	76,856
2020	6,824
2021	5,613
2022	3,548
Thereafter	122,322
Total term debt	228,560
Less: current portion	13,397
Noncurrent	$ 215,163

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))
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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