Commitments and contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments And Contingencies Disclosure [Abstract]

Schedule of Future Minimum Revenues to be Received on Committed Agreements

At December 31, 2018, the minimum future revenues to be received on committed time-charter party agreements and interest income from direct financing leases are as follows:

2019	$	1,094,608
2020		977,926
2021		844,261
2022		688,537
2023		469,754
Thereafter		751,473
	$	4,826,559

Schedule of Commitment Under Operating Leases

Total commitments under these leases are as follows:

2019	$	159,976
2020		159,171
2021		158,326
2022		151,696
2023		150,760
Thereafter		507,546
	$	1,287,475