Leases (Schedule of Lease Costs and Other Lease Information) (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Operating lease
Operating lease cost	$ 182,000	$ 330,000
Short-term lease cost	120,000	240,000
Variable lease cost	18,000	45,000
Sublease income
Total lease cost	320,000	615,000
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	207,000	357,000
Lease right-of-use assets obtained in exchange for new lease liabilities
Lease right-of-use assets obtained in exchange for new lease liabilities - operating leases	$ 535,000	$ 2,215,000