Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- References

No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

No definition available.

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- Definition

Amount of expenses related to the generation of investment income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Financial Instruments and Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Feb. 28, 2018	Dec. 31, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Carrying amount of notes	$ 248,200	$ 248,200			$ 297,900
Mortgage indebtedness	1,428,025	1,428,025			641,082
Mortgages indebtedness [Member]
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Mortgage indebtedness	1,270,000	1,270,000
Interest Rate Cap [Member]
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Notional amount	1,270,000	1,270,000
Fair value of interest rate cap	4,800	4,800
Investment income	400	200
Interest Rate Cap [Member] \| Mortgages indebtedness [Member]
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Mortgage indebtedness			$ 1,350,000	$ 1,350,000
Level 3 [Member]
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Approximate fair value of notes	$ 249,100	$ 249,100			$ 299,000