Store Acquisitions (Detail) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020 USD ($) store	Jun. 30, 2020 USD ($) store	Mar. 31, 2020 USD ($) store	Sep. 30, 2019 USD ($) store	Jun. 30, 2019 USD ($) store	Mar. 31, 2019 USD ($) store	Sep. 30, 2020 USD ($) store	Sep. 30, 2019 USD ($) store
Real Estate [Abstract]
Number of Stores | store	8	0	2	1	1	14	10	16
Total Consideration Paid	$ 101,731	$ 0	$ 19,399	$ 16,937	$ 8,424	$ 223,740	$ 121,130	$ 249,101
Cash Paid	86,996	0	19,354	16,941	8,424	202,890	106,350	228,255
Loan Assumed	0	0	0	0	0	17,157	0	17,157
Finance Lease Liability	13,833	0	0	0	0	0	13,833	0
Investments in Real Estate Ventures	0	0	0	0	0	2,780	0	2,780
Net Liabilities/ (Assets) Assumed	$ 902	$ 0	$ 45	$ (4)	$ 0	$ 913	$ 947	$ 909
Number of stores acquired, previously held noncontrolling interest | store						12
Number of stores acquired, subject to finance land leases | store	2