Environmental Obligations - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Jul. 31, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Commitments [Line Items]
Pollution legal liability insurance policy duration	10 years
Pollution legal liability insurance policy aggregate limit	$ 50,000,000
Remediation agreement of lease		We have agreed to be responsible for environmental contamination at the premises that was known at the time the lease commenced, and which existed prior to commencement of the lease and is discovered (other than as a result of a voluntary site investigation) during the first ten years of the lease term (or a shorter period for a minority of such leases).
Environmental remediation liability		$ 74,516,000	$ 84,345,000
Accretion expense		4,107,000	4,829,000	$ 3,046,000
Amounts of credits to environmental expenses included in continuing and discontinued operations		7,007,000	4,639,000	2,756,000
Increase in carrying value of property		11,346,000	12,285,000
Non-cash impairment charges		$ 11,658,000	12,548,000
Estimated remaining useful life of underground storage tank for capitalized asset retirement costs		10 years
Depreciation and amortization expense for capitalized asset retirement costs		$ 5,126,000	5,997,000	$ 1,560,000
Capitalized asset retirement costs		49,125,000	51,393,000
Asset retirement obligations removed from balance sheet		13,769,000
Deferred rental revenue		$ 2,961,000
Minimum [Member]
Other Commitments [Line Items]
Environmental remediation liability discount range		4.00%
Environmental remediation liability fair value, expected future net cash flows		2.00%
Maximum [Member]
Other Commitments [Line Items]
Environmental remediation liability discount range		7.00%
Environmental remediation liability fair value, expected future net cash flows		2.75%
USTs [Member]
Other Commitments [Line Items]
Asset retirement obligations removed from balance sheet		$ 13,769,000
Net asset cost related to USTs removed from the balance sheet		10,808,000
Deferred rental revenue		2,961,000
Future Environmental Liabilities for Preexisting Unknown Contamination [Member]
Other Commitments [Line Items]
Environmental remediation liability		45,009,000	45,443,000
Non-cash impairment charges		191,000	2,150,000
Capitalized asset retirement costs		28,489,000	30,454,000
Reasonably Estimable Environmental Remediation Obligation [Member]
Other Commitments [Line Items]
Environmental remediation liability		29,507,000	38,902,000
Known Environmental Liabilities [Member]
Other Commitments [Line Items]
Non-cash impairment charges		11,467,000	10,398,000
Capitalized asset retirement costs		$ 20,636,000	$ 20,939,000