Obligations under capital lease (Schedule of Long-term Portion of Minimum Lease payment) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013	$ 1,146
2014	4,582
2015	4,582
2016	4,582
2017	6,910
Thereafter	5,189
Less: Interest	(4,169)
Net minimum lease payments under capital lease	22,822
Less: Current portion of net minimum lease payments	(4,449)
Long-term portion of net minimum lease payments	$ 18,373

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Amount of minimum lease payments maturing in the next fiscal year following the latest fiscal year for capital leases.

+ References

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 maturing in the fifth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the forth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the second fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing after the fifth fiscal year following the latest fiscal year for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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The amount, during the lease term, of each minimum [capital] lease payment allocated to interest expense so as to produce a constant periodic rate of interest on the remaining balance of the capital lease obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 35

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6916424&loc=d3e43161-112731

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The total current contractually required rental payments on capitalized lease

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No definition available.

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The total contractually required rental payments on capitalized leases net of current portion of lease payments

+ References

No definition available.

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