Debt and obligations under capital lease - Long term debt maturities, including obligations under capital leases (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Remainder of 2017	$ 48,153
2018	6,307
2019	118,326
2020	6,329
2021	6,094
2022	6,045
2023	6,045
2024 and thereafter	460,278
Total long-term debt and obligations under capital lease	$ 657,577	$ 602,102

Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal after Year Seven

No definition available.

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- Definition

Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Seven

+ References

No definition available.

+ Details

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- Definition

Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Six

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- References

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- Definition

Principal amount of long-term debt and capital lease obligation maturing 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.

+ References

No definition available.

+ Details

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the fourth 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.

+ References

No definition available.

+ Details

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the third 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.

+ References

No definition available.

+ Details

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the second 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.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt and capital lease obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

+ References

No definition available.

+ Details

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