CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 343,096	$ 268,315	$ 355,131
Other Comprehensive Income (Loss):
Foreign Currency Translation Adjustment	45,779	11,994	(164,107)
Change in Fair Value of Derivative Instruments	(39,947)	(8,783)	(973)
Total Other Comprehensive Income (Loss)	5,832	3,211	(165,080)
Comprehensive Income (Loss)	348,928	271,526	190,051
Comprehensive (Loss) Income Attributable to Noncontrolling Interests	(453)	1,066	(2,207)
Comprehensive Income (Loss) Attributable to Iron Mountain Incorporated	$ 349,381	$ 270,460	$ 192,258