Basis and Summary of Significant Accounting Policies - Related Party Transactions (Details) - Related Party $ in Millions	6 Months Ended	36 Months Ended
Jun. 30, 2018 USD ($) lease	Dec. 31, 2004 Property
Related Party Transaction [Line Items]
Sale leaseback, number of properties \| Property		21
Number of capital leases	7
Number of operating leases	10
Leases under renegotiation	16
Capital leases, annual rental payments \| $	$ 0.4
Interest rate in the leases	9.70%
Operating leases, annual rental payments \| $	$ 0.8

The yearly payments due under the lease entered into in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84164451&loc=d3e36991-112694

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755

Name:	us-gaap_SaleLeasebackTransactionAnnualRentalPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration