Lease Obligations - Schedule of Lease Costs including Weighted Average Lease Terms and Weighted-average Discount Rates (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Finance cost:
Interest on lease liability (included in Interest expense, net)	$ 411	$ 821
Short-term lease cost	17	44
Variable lease cost	61	134
Sublease income (included in Rentals, net)	(6,754)	(13,534)
Total lease cost	$ (5,399)	$ (10,802)
Operating lease, weighted average remaining lease term (in years)	42 years 1 month 6 days	42 years 1 month 6 days
Financelease, weighted average remaining lease term (in years)	4 years 6 months	4 years 6 months
Operating lease, weighted average discount rate, percent	4.90%	4.90%
Finance lease, weighted average discount rate, percent	7.50%	7.50%
Operating expense [Member]
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 761	$ 1,522
General and administrative expense [Member]
Lessee, Lease, Description [Line Items]
Operating lease cost	67	128
Depreciation and Amortization [Member]
Finance cost:
Amortization of right-of-use asset (included in Depreciation and Amortization)	$ 38	$ 83