Lease financing - Capital lease obligations, Principal payments (Table) (Details) - Financing Lease [Member] $ in Thousands	Jun. 30, 2021 USD ($)
Obligation with Joint and Several Liability Arrangement [Line Items]
June 30, 2022	$ 54,723
June 30, 2023	54,723
June 30, 2024	49,950
June 30, 2025	49,723
June 30, 2026	124,318
June 30, 2027 and thereafter	171,017
Total bareboat lease minimum payments	504,454
Unamortized lease issuance costs	(6,194)
Total bareboat lease minimum payments, net	498,260
Lease financing short term	54,723
Lease financing long term, net of unamortized lease issuance costs	$ 443,537

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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