Facility Leases (Narrative) (Details) - Subsequent Event [Member] $ in Millions	1 Months Ended
	May. 31, 2016 USD ($) ft²
Gaithersburg, Maryland [Member]
Facility Lease Term	2030
Rental Square Footage of Building | ft²	150,000
Tenant Improvement Allowance | $	$ 9.6
Rockville, Maryland [Member]
Facility Lease Term	2020