Leases

12 Months Ended

Dec. 31, 2018

(a) Capital Leases

The following is an analysis of the leased property under capital leases by major class (in thousands):


	Asset Balances at December 31,
Class of property	2018		2017
Lab equipment	$	720	$	720
Leasehold improvements	27		27
Computer equipment	54		54
Total property under capital leases	801		801
Less accumulated depreciation and amortization	(703)		(652)
Capital leased assets, net	$	98	$	149

The depreciation and amortization reflected above has been recorded in both research and development and general administrative expense in the consolidated statements of operations.

We have no future minimum lease payments under capital leases as of December 31, 2018.

(b) Operating Leases

The Company has certain facility leases with non-cancellable terms ranging between one and three years, with certain renewal options. Lease expense is recognized on a straight-line basis. Rental expense for operating leases during the years ended December 31, 2018, 2017 and 2016, was $1.1 million, $1.2 million, and $1.7 million, respectively, including those with terms less than one year, and has been included in both research and development and general and administration in the consolidated statements of operations.

Future minimum lease payments under the noncancelable operating leases (with initial or remaining lease terms in excess of one year), with certain renewal options, as of December 31, 2018 are as follows (in thousands):


Year Ending December 31:
2019	$	1,105
2020	1,004
2021	923
2022	906
2023	909
Thereafter	6,570
Total	$	11,417