Acquisitions (Details)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Combinations [Abstract]
Number of stores purchased	1	12

The number of businesses acquired by the entity during the period.

No definition available.

Name:	us-gaap_NumberOfBusinessesAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration