Summary of Significant Accounting Policies (Details 3) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Summary Of Significant Accounting Policies [Line Items]
Long-lived assets held and used	$ 1,307	$ 7,110
Long-lived assets held for sale	15,711	14,761
Total nonrecurring for value measurements	17,018	21,871
Long-lived assets held and used, Loss	675	12,264
Long-lived assets held for sale, Loss		14,290
Total nonrecurring for value measurements, Loss	675	26,554
Quoted prices in active markets for identical assets (Level 1) [Member]
Summary Of Significant Accounting Policies [Line Items]
Long-lived assets held and used
Long-lived assets held for sale
Total nonrecurring for value measurements
Significant other observable inputs (Level 2) [Member]
Summary Of Significant Accounting Policies [Line Items]
Long-lived assets held and used	1,307	7,110
Long-lived assets held for sale	15,711	14,761
Total nonrecurring for value measurements	17,018	21,871
Significant unobservable inputs (Level 3) [Member]
Summary Of Significant Accounting Policies [Line Items]
Long-lived assets held and used
Long-lived assets held for sale
Total nonrecurring for value measurements