Significant Transactions During the Six Months Ended June 30, 2022 and Subsequent Events (Details) $ / shares in Units, $ in Millions	1 Months Ended					3 Months Ended
	Jun. 30, 2022 USD ($)	Apr. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Jan. 31, 2022 USD ($) apartment	Nov. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) investment
Other Commitments [Line Items]
Shares repurchased and retired during period (in shares) | shares						218,960
Shares repurchased and retired during period, value						$ 60.8
Treasury stock acquired, average cost per share (in dollars per share) | $ / shares						$ 277.81
Purchase authority remaining under stock repurchase plan	$ 153.6					$ 153.6
Stock repurchase plan amount	250.0					$ 250.0
Related Party Bridge Loan on Property In Vista, CA
Other Commitments [Line Items]
Proceeds from redemption of notes receivable				$ 48.5
Affiliated Entity | Related Party Bridge Loan on Property In Vista, CA
Other Commitments [Line Items]
Notes receivable					$ 48.4
Interest rate					2.36%
Affiliated Entity | Related Party Bridge Loan On Property Acquired By BEX II
Other Commitments [Line Items]
Notes receivable			$ 32.8		$ 32.8		$ 32.8
Interest rate			1.35%		1.35%
Wesco IV
Other Commitments [Line Items]
Limited partnership interest in partnership investments		65.10%
Promote interest		$ 37.5
Preferred Equity Investment Property In Northern California
Other Commitments [Line Items]
Proceeds from partial redemption of co-investment	$ 3.0
Preferred Equity Investment Property in Southern California and Washington
Other Commitments [Line Items]
Number of preferred equity investments | investment							3
Commitments to acquire equity method investment							$ 29.5
Preferred return rate							10.00%
Joint Venture That Holds Property In California
Other Commitments [Line Items]
Proceeds from partial redemption of co-investment							$ 106.9
Early redemption fee							$ 0.9
Number of preferred equity investments fully redeemed | investment							2
Number of preferred equity investments partially redeemed | investment							2
Vela On Ox | Affiliated Entity | Related Party Bridge Loan on Property Acquired By Wesco VI
Other Commitments [Line Items]
Notes receivable				$ 100.7
Interest rate				2.64%
Proceeds from redemption of notes receivable				$ 121.3
Vela On Ox | Wesco VI
Other Commitments [Line Items]
Payments to acquire real estate				$ 183.0
Vela On Ox | Apartment Building | Wesco VI
Other Commitments [Line Items]
Number of units acquired | apartment				379