Revenue Recognition (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue Recognition [line items]
Medicare cap		$ 0		$ 0
Percentage of automatic budget reductions							2.00%
Unbilled Revenue	$ 1,900,000		$ 1,900,000
Two Program Projected Measurement Period Liability [Member]
Revenue Recognition [line items]
Medicare cap	247,000		247,000
Additional amount owed for Medicare cap					$ 2,200,000	$ 2,200,000	$ 2,200,000
Sequestration [Member]
Revenue Recognition [line items]
Medicare cap	$ 105,000		$ 105,000