Summary of Significant Accounting Policies West Advantage Customer Loyalty Program (Details) - USD ($) $ in Millions	Dec. 31, 2016	Jan. 02, 2016
Accounting Policies [Abstract]
Customer Loyalty Program Liability, Current	$ 1.3	$ 1.3

Value of deferred revenue or cost to provide products or services, which is expected to be recognized in income or incurred within one year or the normal operating cycle, if longer, resulting from customer loyalty program. Excludes liability associated with frequent flier programs. Includes liability associated with customer loyalty programs for other businesses, for example, but is not limited to, hotels, supermarkets, credit card companies, automobile rental companies, and book sellers.

No definition available.

Name:	us-gaap_CustomerLoyaltyProgramLiabilityCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant