Leases

3 Months Ended

Mar. 31, 2021

We have operating leases for our office and laboratory facilities, including our corporate headquarters, with terms that expire from 2025 through 2031. We have two options to extend the term of the operating lease for our corporate headquarters for a period of ten years each. However, as we were not reasonably certain to exercise either of those options at lease commencement, neither option was recognized as part of the associated operating lease right-of-use, or ROU, asset or liability. In connection with our operating leases, in lieu of cash security deposits, Wells Fargo Bank, N.A., issued letters of credit on our behalf, which are secured by deposits totaling $3.2 million.

Our operating lease cost was $3.4 million and $2.5 million for the three months ended March 31, 2021 and 2020, respectively. Cash paid for amounts included in the measurement of lease liabilities was $2.6 million and $2.1 million for the three months ended March 31, 2021 and 2020, respectively.

Our operating leases had a weighted average remaining lease term of 9.8 years at March 31, 2021 and 10.3 years at December 31, 2020, and a weighted average discount rate of 5.3% at March 31, 2021 and 5.6% at December 31, 2020.

Approximate future minimum lease payments under operating leases were as follows:


(in millions)	March 31, 2021
Year ending December 31, 2021 (9 months remaining)	$	9.1
Year ending December 31, 2022	14.9
Year ending December 31, 2023	15.5
Year ending December 31, 2024	16.0
Year ending December 31, 2025	15.5
Thereafter	85.4
Total operating lease payments	156.4
Less accreted interest	36.7
Total operating lease liabilities	119.7
Less current operating lease liabilities	12.2
Noncurrent operating lease liabilities	$	107.5

(1) Amounts presented in the table above exclude $5.8 million of non-cancelable future minimum lease payments for operating leases that have not yet commenced.

(2) Current operating lease liabilities are included in other current liabilities on the condensed consolidated balance sheets.