Commitments and Contingencies (Details)	1 Months Ended				2 Months Ended	9 Months Ended
	Jun. 30, 2017 defendant	Mar. 31, 2017 lawsuit	Sep. 30, 2015 pharmacy	Feb. 28, 2006 item lawsuit director	Sep. 30, 2017 complaint store	Sep. 30, 2017 item store
Loss contingencies
Number of store leases guaranteed | store					86	86
Number of material accruals for outstanding legal matters						0
Number of pharmacies indicated in subpoena | pharmacy			8
Number of lawsuits | lawsuit		4
Number of legal proceedings, government investigations, inquiries and audits expected to be material						0
Omnicare, Inc.
Loss contingencies
New claims filed, number | lawsuit				2
Number of officers named in lawsuit				3
Number of directors named in lawsuit | director				2
Cherokee Nation Opioid Litigation
Loss contingencies
Number of defendants | defendant	6
Shareholder Matters
Loss contingencies
Number of complaints | complaint					4
Number of complaints filed in Rhode Island | complaint					3