We have operating leases for facilities used for manufacturing, research and development, sales and distribution, and office space, as well as leases for manufacturing and office equipment, vehicles, and land. Our leases have remaining terms ranging from less than one year to approximately 28 years. A number of our lease agreements contain options to renew at our discretion for periods of up to 15 years and options to terminate the leases within one year. The lease term used to calculate ROU assets and lease liabilities includes renewal and termination options that are deemed reasonably certain to be exercised. Lease agreements with lease and non-lease components are generally accounted for as a single lease component. We do not have any bargain purchase options in our leases. For leases with an initial term of one year or less, we do not record a ROU asset or lease liability on our consolidated balance sheet. Substantially all of the ROU assets and lease liabilities as of December 31, 2021 recorded on our consolidated balance sheet are related to our cardiovascular segment.

From time to time, we enter into agreements to sublease a portion of our facilities to third parties. Such sublease income is not material. We also lease certain hardware consoles to customers and record rental revenue as a component of net sales. Rental revenue under such console leasing arrangements for the years ended December 31, 2021, 2020 and 2019 was not significant.

The following was included in our consolidated balance sheet as of December 31, 2021 and 2020 (in thousands):

During the year ended December 31, 2015, we entered into sale and leaseback transactions to finance certain production equipment for $2.0 million. At that time, we deferred the gain from the sale and leaseback transaction, of which $93,000 remained as of December 31, 2018. As part of the adoption of ASC 842, we wrote-off the deferred gain as an adjustment to equity through retained earnings as of January 1, 2019.

We recognize lease expense for operating leases on a straight-line basis over the term of the lease. Net lease cost for the years ended December 31, 2021, 2020 and 2019 was $15.9 million, $16.7 million, and $16.5 million, respectively. The components of lease costs for the years ended December 31, 2021, 2020 and 2019 were as follows, in thousands:


(a)	Includes expense related to short-term leases and variable payments, which were not significant.

(b)		Does not include rental revenue from leases of hardware consoles to customers, which was not significant.

Supplemental cash flow information for the years ended December 31, 2021, 2020 and 2019 was as follows, in thousands:


	2021		2020		2019
Cash paid for amounts included in the measurement of lease liabilities	$	14,970		15,059		14,646
Right-of-use assets obtained in exchange for lease obligations	$	1,524		10,938		10,637

Generally, our lease agreements do not specify an implicit rate. Therefore, we estimate our incremental borrowing rate, which is defined as the interest rate we would pay to borrow on a collateralized basis, considering such factors as length of lease term and the risks of the economic environment in which the leased asset operates. As of December 31, 2021, 2020 and 2019, our lease agreements had the following remaining lease term and discount rates:


	2021	2020	2019
Weighted average remaining lease term	11.4 years	11.5 years	12.3 years
Weighted average discount rate	3.4%	3.3%	3.2%

As of December 31, 2021, maturities of operating lease liabilities were as follows, in thousands:


Year ended December 31,	Amounts due under operating leases
2022	$	12,405
2023		9,794
2024		8,847
2025		7,130
2026		6,378
Thereafter		43,306
Total lease payments		87,860
Less: Imputed interest		(15,666)
Total	$	72,194

As of December 31, 2021, we had additional operating leases for office space that had not yet commenced. These leases will commence during 2022 and are not deemed material.