Segment Information - Revenues with a Reconciliation to Income (Loss) before Income Tax and Gain (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
	Sep. 15, 2016	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment revenues:
Revenues		$ 415,817	$ 402,010	$ 394,667	$ 391,141	$ 401,721	$ 389,501	$ 379,451	$ 372,914	$ 1,603,635	$ 1,543,587	$ 1,489,999
Segment contribution:
Operating income		$ 51,171	$ 43,553	$ 49,304	$ 35,932	$ 44,054	$ 27,442	$ 28,707	$ 36,786	179,960	136,989	132,124
Reconciling items:
Depreciation, depletion, and amortization										(117,653)	(116,741)	(118,571)
Impairment of long-lived assets										(747)	(9,473)	(9,820)
Selling, general and administrative expense										(114,760)	(110,945)	(96,728)
Loss from partially owned entities										(1,069)	(1,363)	(128)
Gain from sale of real estate, net										7,471	43	11,598
Impairment of partially owned entities										0	(6,496)	0
Interest expense	$ (300)									(93,312)	(114,898)	(119,552)
Interest income										3,996	1,074	708
Loss on debt extinguishment, modifications and termination of derivative instruments										(47,559)	(986)	(1,437)
Foreign currency exchange gain (loss), net										2,882	(3,591)	464
Other expense, net										(532)	(1,944)	(1,368)
Income before income tax benefit (expense)										44,366	8,785	10,811
Operating Segments
Segment revenues:
Revenues										1,603,635	1,543,587	1,489,999
Segment contribution:
Operating income										405,649	374,105	345,645
Operating Segments | Warehouse
Segment revenues:
Revenues										1,176,912	1,145,662	1,080,867
Segment contribution:
Operating income										374,534	348,328	314,045
Operating Segments | Third-party managed
Segment revenues:
Revenues										259,034	242,189	252,411
Segment contribution:
Operating income										14,760	12,825	14,814
Operating Segments | Transportation
Segment revenues:
Revenues										158,790	146,070	147,004
Segment contribution:
Operating income										15,735	12,950	14,418
Operating Segments | Other
Segment revenues:
Revenues										8,899	9,666	9,717
Segment contribution:
Operating income										$ 620	$ 2	$ 2,368