Leases (Summary of Lease Costs and Other Lease Information (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
		Jun. 30, 2019	Jun. 30, 2019
Lease costs:
Operating lease costs		$ 697	$ 1,390
Variable lease costs	[1]	113	209
Sublease income		(11)	(23)
Net lease costs		$ 799	1,576
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases			1,332
Right of use assets obtained in exchange for new operating lease liabilities			$ 346

[1] Variable lease costs primarily represent variable payments such as common area maintenance, insurance, taxes and utilities.