Summary of Critical and Significant Accounting Policies - AOCI (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	$ 6,183,192
Other comprehensive income before reclassification	9,161
Amounts reclassified from accumulated other comprehensive loss	16
Other comprehensive income	9,177
Balance at December 31, 2021	6,176,508
Accumulated other comprehensive loss, net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	(14,729)
Balance at December 31, 2021	(5,552)
Change in fair value and amortization of swap settlements
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	(14,771)
Other comprehensive income before reclassification	8,843
Amounts reclassified from accumulated other comprehensive loss	16
Other comprehensive income	8,859
Balance at December 31, 2021	(5,912)
Unrealized gain on available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	42
Other comprehensive income before reclassification	318
Amounts reclassified from accumulated other comprehensive loss	0
Other comprehensive income	318
Balance at December 31, 2021	360
Essex Portfolio, L.P.
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income before reclassification	9,482
Amounts reclassified from accumulated other comprehensive loss	17
Other comprehensive income	9,499
Essex Portfolio, L.P. | Accumulated other comprehensive loss, net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	(11,303)
Balance at December 31, 2021	(1,804)
Essex Portfolio, L.P. | Change in fair value and amortization of swap settlements
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	(11,346)
Other comprehensive income before reclassification	9,153
Amounts reclassified from accumulated other comprehensive loss	17
Other comprehensive income	9,170
Balance at December 31, 2021	(2,176)
Essex Portfolio, L.P. | Unrealized gain on available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at December 31, 2020	43
Other comprehensive income before reclassification	329
Amounts reclassified from accumulated other comprehensive loss	0
Other comprehensive income	329
Balance at December 31, 2021	$ 372