The Company is subject to various non-cancelable operating leases for office space and IT equipment expiring at various dates through November 2022. These leases do not have significant rent escalation, holidays, concessions, leasehold improvement incentives, or other build-out clauses. Further, the leases do not contain contingent rent provisions.

Most of these leases include an option to renew. The exercise of lease renewal options is typically at our sole discretion; therefore, the majority of renewals to extend the lease terms are not included in our right-of-use ("ROU") assets and lease liabilities because they are not reasonably certain of exercise. We regularly evaluate the renewal options and, when they are reasonably certain of exercise, we include the renewal period in our lease term.

Because most of our leases do not provide an implicit rate, we use our incremental borrowing rate in determining the present value of the lease payments. The incremental borrowing rate represents an estimate of the interest rate we would incur at lease commencement to borrow an amount equal to the lease payments on a collateralized basis over the term of a lease. We used incremental borrowing rates as of January 1, 2019 for operating leases that commenced prior to that date. We have a centrally managed treasury function; therefore, based on the applicable lease terms and the current economic environment, we apply a portfolio approach for determining the incremental borrowing rate.

The cost components of our operating leases were as follows (in thousands):

	Three-Month Periods Ended June 30,				Six-Month Periods Ended June 30,
	2021		2020		2021		2020
Operating lease costs	$	53	$	65	$	108	$	131
Variable lease cost		51		93		93		169
Total	$	104	$	158	$	201	$	300

Variable lease costs consist primarily of property taxes, insurance, and common area or other maintenance costs for our leased facilities and equipment, which are paid based on actual costs incurred by the lessor.

Maturities for our lease liabilities for all operating leases were as follows (in thousands) as of June 30, 2021:

	Total
2021	$	26
2022		4
2023 and thereafter		—
Total lease payments		30
Less: Interest		(1	)
Present value of lease liabilities	$	29

The weighted average remaining lease terms and discount rates for all of our operating leases were as follows as of June 30, 2021:

	June 30, 2021
Remaining lease term and discount rate:
Weighted average remaining lease term (years)	0.68
Weighted average discount rate	4.75	%

Cash paid for amounts included in the measurement of operating lease liabilities was $107,000 and $134,000 for the six months ended June 30, 2021 and 2020, respectively, and these amounts are included in operating activities in the condensed consolidated statements of cash flows. There were no operating lease assets obtained in exchange for new operating lease liabilities for the three and six months ended June 30, 2021 and 2020, except that during the three months ended June 30, 2020, we agreed to a one-year extension of our office space which increased operating lease assets and liabilities by $194,000.

On July 28, 2021 ISNS and Spruce Tree Centre L.L.P. entered into Amendment XV to Office Lease Agreement (the "Amendment"), which amended the original Office Lease Agreement dated as of November 24, 1998 by and between ISNS and Spruce Tree (the "Original Lease"), as such Original Lease was subsequently amended (as so amended, the "Lease"). The Amendment was signed by Spruce Tree on July 28, 2021. The Lease term was to expire on July 31, 2021. The Amendment, which is effective August 1, 2021, extends the Lease through March 31, 2022. In addition, the Amendment increases the monthly rent from $16,660 to $16,960 for the period from August 1, 2021 through March 31, 2022.