Subsequent Event - Additional Information (Detail) $ in Millions		1 Months Ended
Nov. 03, 2017 USD ($) ft² Option	Dec. 31, 2015 Option
Subsequent Event [Line Items]
Number of lease term extension options \| Option		2
Subsequent Event [Member] \| Lease Agreement [Member] \| California [Member] \| Marina Boulevard Property, LLC [Member]
Subsequent Event [Line Items]
Rentable area of building \| ft²	87,695
Description of lease term	Unless earlier terminated, the term of the Lease (the “Initial Term”) will commence on June 1, 2018 (the “Commencement Date”) and will expire the day before the eleventh anniversary of the Commencement Date.
Lease commencement date	Jun. 01, 2018
Aggregate base rent due over initial term	$ 38
Estimated additional rent during the initial term	10
Expected leasehold improvements net of tenant improvement allowance	$ 15
Number of lease term extension options \| Option	2
Lease renewal term	5 years
Percentage of market rent on commencement of applicable renewal term	90.00%

Description of lease term.

No definition available.

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- Definition

Leasehold improvements net of tenant improvement allowance.

+ References

No definition available.

+ Details

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- Definition

Operating lease commencement date.

+ References

No definition available.

+ Details

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- Definition

Operating leases number of extension options.

+ References

No definition available.

+ Details

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- Definition

Percentage of market rent on commencement of renewal term.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(15)(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

+ Details

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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