Real Estate - Summary of Dispositions of Net Investments in Real Estate (Detail) ft² in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) ft² Property	Dec. 31, 2019 USD ($) ft² Property	Dec. 31, 2018 USD ($) ft² Property
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total gains on other dispositions of investments in real estate, net	$ 67,838	$ 108,927	$ 43,939	$ 31,491	$ 157,841	$ 59,379	$ 27,254	$ 145,767	$ 252,195	$ 390,241	$ 371,179
Discontinuing Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings | Property									41	31	44
Square feet | ft²									14,482	10,027	15,527
Net proceeds									$ 1,693,557	$ 1,533,055	$ 1,803,240
Gains on contributions and dispositions, net									464,942	467,577	469,817
Total gains on dispositions of development properties and land, net									$ 464,942	$ 467,577	$ 469,817
Continuing Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings | Property									61	66	74
Square feet | ft²									10,562	15,816	13,035
Net proceeds									$ 1,264,692	$ 1,492,212	$ 956,676
Gains on contributions and dispositions, net									252,195	255,219	371,179
Continuing Operations [Member] | Partial redemptions of investments in co-investment ventures [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gains on contributions and dispositions, net									$ 0	$ 135,022	$ 0