Financial Income and Expenses - Additional Information (Details) € in Thousands	12 Months Ended
Dec. 31, 2020 EUR (€)
Disclosure Of Financial Income And Expenses [Line Items]
Foreign currency exchange loss	€ 8,525
OCEANEs
Disclosure Of Financial Income And Expenses [Line Items]
Percentage of payment of coupons rate	3.50%
Percentage of discount of bond debt at effective interest rate	7.20%

Amount before tax of foreign currency transaction realized and unrealized loss recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894

Name:	us-gaap_ForeignCurrencyTransactionLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration