Investments in Real Estate - Schedule of Purchase Price Allocation of Properties (Detail) $ in Thousands	Sep. 30, 2018 USD ($)
Real Estate Properties [Line Items]
Building and building improvements	$ 4,467,011
Land and land improvements	1,161,994
Furniture, fixtures and equipment	88,048
In-place lease intangibles	259,711
Above-market lease intangibles	11,924
Below-market lease intangibles	(33,121)
Above-market ground lease intangible	(4,657)
Other	5,481
Total purchase price	5,956,391
Assumed mortgage notes	197,290
Non-controlling interest	12,802
Net purchase price	5,746,299
Canyon Industrial Portfolio [Member]
Real Estate Properties [Line Items]
Building and building improvements	1,362,916
Land and land improvements	376,762
In-place lease intangibles	109,031
Above-market lease intangibles	8,459
Below-market lease intangibles	(19,955)
Total purchase price	1,837,213
Net purchase price	1,837,213
EdR Student Housing Portfolio [Member]
Real Estate Properties [Line Items]
Building and building improvements	1,034,732
Land and land improvements	138,249
Furniture, fixtures and equipment	11,072
In-place lease intangibles	51,583
Below-market lease intangibles	(122)
Above-market ground lease intangible	(4,657)
Total purchase price	1,230,857
Assumed mortgage notes	46,070
Non-controlling interest	12,802
Net purchase price	1,171,985
JW Marriott San Antonio Hill Country Resort [Member]
Real Estate Properties [Line Items]
Building and building improvements	474,529
Land and land improvements	84,218
Furniture, fixtures and equipment	39,979
In-place lease intangibles	597
Other	5,000
Total purchase price	604,323
Net purchase price	604,323
Wave Multifamily Portfolio [Member]
Real Estate Properties [Line Items]
Building and building improvements	323,954
Land and land improvements	82,686
Furniture, fixtures and equipment	5,252
In-place lease intangibles	11,243
Total purchase price	423,135
Net purchase price	423,135
All Other [Member]
Real Estate Properties [Line Items]
Building and building improvements	1,270,880
Land and land improvements	480,079
Furniture, fixtures and equipment	31,745
In-place lease intangibles	87,257
Above-market lease intangibles	3,465
Below-market lease intangibles	(13,044)
Other	481
Total purchase price	1,860,863
Assumed mortgage notes	151,220
Net purchase price	$ 1,709,643

Above-market ground lease intangible acquired and allocated.

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Above market lease intangible acquired and allocated.

+ References

No definition available.

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- Definition

Asset acquisitions, purchase price allocation of real estate properties.

+ References

No definition available.

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- Definition

Asset acquisitions, recognized identifiable assets acquired and liabilities assumed mortgage notes payable.

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Below market lease intangibles acquired and allocated.

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- Definition

Fixtures and equipment gross purchase price allocation.

+ References

No definition available.

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- Definition

Investment building and building improvements purchase price allocation.

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- Definition

Land and land improvements purchase price allocation.

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No definition available.

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- Definition

This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

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Amount after accumulated amortization of finite-lived and indefinite-lived intangible assets classified as other.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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