CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 40,730	$ 21,411	$ 104,040	$ 54,961
Other comprehensive income (loss)
Unrealized gain (loss) on derivative contracts	243	(562)	14,418	(77,354)
Reclassification of other comprehensive loss to interest expense	5,242	4,973	15,323	9,519
Other comprehensive income (loss)	5,485	4,411	29,741	(67,835)
Comprehensive income (loss)	46,215	25,822	133,781	(12,874)
Comprehensive income attributable to noncontrolling interests	(12,009)	(9,323)	(33,304)	(146)
Comprehensive income (loss) attributable to National Storage Affiliates Trust	$ 34,206	$ 16,499	$ 100,477	$ (13,020)