Accrued management and incentive fees payable.

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- Definition

Management agreement initial term expiry date.

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No definition available.

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Management agreement renewal period.

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Management agreement renewal term description.

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- Definition

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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- Definition

Amount of expense for administrative services provided to the limited liability company (LLC) or limited partnership (LP) by the managing member or general partner, affiliate of managing member or general partner, or affiliate of LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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- Definition

Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
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- Definition

Professional and contract service expense includes cost reimbursements for support services related to contracted projects, outsourced management, technical and staff support.

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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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No definition available.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Transactions with Related Parties - Additional Information (Detail) £ in Millions, € in Billions	3 Months Ended
	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($)	Mar. 31, 2019 GBP (£) shares	Dec. 31, 2018 USD ($) shares	Mar. 31, 2018 EUR (€)
Related Party Transaction [Line Items]
Common stock value	$ 1,257,000			$ 1,234,000
Non-cash expenses	$ 7,768,000	$ 6,976,000
Restricted Class A Common Stock [Member]
Related Party Transaction [Line Items]
Shares held \| shares	1,782,157		1,782,157	1,614,907
Senior Term Facility [Member]
Related Party Transaction [Line Items]
Loan face amount			£ 490.0		€ 7.3
Senior term facility			£ 240.1		€ 1.0
Minority participation in senior term facility	49.00%	14.00%	49.00%		14.00%
Manager [Member]
Related Party Transaction [Line Items]
Management Agreement expiration date	Dec. 19, 2019
Management Agreement renewal term, description	the current term of which expires on December 19, 2019, and will be automatically renewed for a one-year term upon such date and each anniversary thereafter unless earlier terminated.
Management Agreement renewal term, period	1 year
Accrued management and incentive fees payable	$ 19,800,000			$ 18,600,000
Management fees paid to Manager	18,600,000	$ 14,300,000
Expenses reimbursed to Manager	$ 188,000	190,000
Manager [Member] \| Senior Loan [Member]
Related Party Transaction [Line Items]
Loan face amount		330,000,000
Manager [Member] \| Class A Common Stock [Member] \| Restricted Class A Common Stock [Member]
Related Party Transaction [Line Items]
Shares held \| shares	882,524		882,524
Common stock value	$ 27,900,000
Non-cash expenses	3,800,000	3,200,000
Affiliates of Manager [Member] \| Third-Party Service Provider [Member]
Related Party Transaction [Line Items]
Administrative services expenses incurred	$ 86,000	$ 141,000
Blackstone-Advised Investment Vehicles, or the Funds [Member] \| Senior Term Facility [Member]
Related Party Transaction [Line Items]
Ownership interest in joint venture		51.00%			51.00%