Financial Instruments and Fair Value Measurement - Narrative (Details) - Fair Value, Inputs, Level 2 - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivables from hedges / derivatives	$ 2	$ 8,436
Prepaid expenses and other current assets	0	8,434
Other financial assets (non-current)	2	1
Liabilities from derivatives	16,911	9,425
Other current liabilities	24	109
Other liabilities (non-current)	16,887	9,316
Term loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of loans	652,138	643,051
Local bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of loans	$ 116,670	$ 29,762

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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