Acquisitions (Details) - stores	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Business Combinations [Abstract]
Number of stores purchased	5	0

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