Goodwill and Other Intangibles (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Other Intangibles
Increase in Goodwill	$ 28,257	$ 758
Goodwill impairment	0	0
Increase in non-compete agreements	1,100	200
Indefinite-lived intangible assets, other than goodwill	0	0
Amortization expense of amortizable intangible assets	$ 2,100	2,700	$ 3,900
Favorable Leases [Member]
Goodwill and Other Intangibles
Weighted-average remaining useful life of favorable leases	8 years 11 months 19 days
Unfavorable Leases [Member]
Goodwill and Other Intangibles
Weighted-average remaining useful life of unfavorable leases	3 years 8 months 26 days
Amortization benefit of unfavorable operating leases	$ 2,100	$ 2,800	$ 3,700