Leases - Summary of Maturity Analysis of Operating and Finance Lease Liabilities and Reconciliation of Undiscounted Cash Flows (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Operating lease payments due:
Within one year	$ 1,042
After one but within two years	1,868
After two but within three years	1,824
After three but within four years	1,572
After four but within five years	1,512
After five years	5,584
Total undiscounted cash flows	13,402
Discount on cash flows	(1,759)
Total lease liability	11,643	$ 12,544
Finance lease payments due:
Within one year	108
After one but within two years	216
After two but within three years	217
After three but within four years	217
After four but within five years	252
After five years	3,992
Total undiscounted cash flows	5,002
Discount on cash flows	(1,493)
Total lease liability	$ 3,509	$ 3,551