Debt (Bank Of America Credit Facility) (Narrative) (Details) - USD ($) $ in Thousands		12 Months Ended
	Mar. 03, 2016	Dec. 31, 2016	Dec. 31, 2015	Nov. 28, 2014	Nov. 27, 2014
Debt Instrument [Line Items]
Contractual facility		$ 266,233	$ 207,075
US Bank Of America Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity				$ 55,000	$ 35,000
Contractual facility	$ 55,000	$ 55,000	$ 55,000
Reduced leverage ratio	0.25%
Minimum [Member] | US Bank Of America Credit Facility [Member]
Debt Instrument [Line Items]
Spread over LIBOR		2.50%
Maximum [Member] | US Bank Of America Credit Facility [Member]
Debt Instrument [Line Items]
Spread over LIBOR		3.00%