The table below presents information about operating lease liabilities as of March 31, 2019, (in thousands, except percentages).

Remainder of 2019	$	65,058
2020		84,120
2021		79,102
2022		78,288
2023		76,386
Thereafter		485,856
Total undiscounted lease payments		868,810
Imputed interest		(198,035	)
Total operating lease liabilities	$	670,775
Weighted average remaining lease term	11.9 years
Weighted average discount rate		4.58	%

In the table above, the weighted average discount rate represents our company’s incremental borrowing rate as of January 2019 for leases existing on the date of adoption of the new lease standard and at the lease inception date for leases entered into subsequent to the adoption of ASU 2016-02.

Operating lease costs, included in occupancy and equipment rental in the consolidated statements of operations, were $21.0 million for the three months ended March 31, 2019 and $21.9 million for the three months ended March 31, 2018.

As of March 31, 2019, the Company had a total lease portfolio of 29 aircraft engines with a net book value of $286.0 million, which is included in fixed assets, net in the consolidated statements of financial condition.

As of March 31, 2019, minimum future payments under non-cancelable leases were (in thousands):

Remainder of 2019	$	25,478
2020		22,099
2021		18,012
2022		10,004
2023		4,889
Thereafter		10,420
	$	90,902

Lease income, included in other income in the consolidated statements of operations, was $8.2 million for the three months ended March 31, 2019.