Leases (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) stores
Leases
Future minimum sublease income under non-cancelable subleases	$ 16.3
Related parties [Member]
Related Parties
Number of stores \| stores	74
Lease payments under related party operating leases	$ 1.2

Amount of transactions with related party during the financial reporting period.

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