Other Noncontrolling Interests - Additional Information (Detail)	Sep. 30, 2018 property joint_venture store
Noncontrolling Interest [Line Items]
Voting interests of third-party owners	9.00%
Other
Noncontrolling Interest [Line Items]
Number of consolidated joint ventures | joint_venture	2
Minimum | Other
Noncontrolling Interest [Line Items]
Voting interests of third-party owners	5.00%
Maximum | Other
Noncontrolling Interest [Line Items]
Voting interests of third-party owners	20.00%
Joint Venture 1
Noncontrolling Interest [Line Items]
Number of operating stores owned | store	2
Joint Venture 2 | Other
Noncontrolling Interest [Line Items]
Number of operating stores owned	1
Number of development stores owned	1