Commitments and contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Minimum Future Rental Payments

Minimum future rental payments, excluding taxes, insurance and other operating expenses, under the noncancelable operating leases in effect at December 31, 2018 are as follows (in thousands):

Year ending December 31:
2019	$	545
2020	230
Total minimum rental payments	$	775