The percentage decrease in the cost of the rental rates under the terms of the lease

No definition available.

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- Definition

Lease extension period.

+ References

No definition available.

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- Definition

Leases.

+ References

No definition available.

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- Definition

Letter of credit issued by the bank in lieu of a cash security deposit under the terms of a lease, secured by a deposit of equal amount with that bank.

+ References

No definition available.

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- Definition

Number of buildings leased.

+ References

No definition available.

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- Definition

The number of renewal options under the terms of the lease.

+ References

No definition available.

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- Definition

Number of vacated buildings.

+ References

No definition available.

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- Definition

The term whereby the Company leased back the property in a sale leaseback transaction involving the sale of the property to another party and the lease of the property back to the Company, in PnY format.

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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

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- Definition

Amount of decrease in 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, from sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Footnote 6))
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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

+ Details

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- Definition

The portion of the deferred gain that was recognized in the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 35
-Paragraph 1
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- Definition

The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

+ References

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- Definition

Amount of cash inflow before closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in investing activities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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- Definition

Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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Leases - Additional Information (Detail) $ in Millions	1 Months Ended		12 Months Ended
Leases - Additional Information (Detail) $ in Millions	Jun. 30, 2017 USD ($)	Dec. 31, 2007 USD ($) Building	Dec. 31, 2018 USD ($) Building RenewalOption	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	May 31, 2018 USD ($) ft²	Dec. 31, 2008 USD ($)
Leases [Line Items]
Sale of facility and associated real property		$ 109.0
Mortgage debt retired		47.7
Cash received net of transaction costs and debt retirement		$ 61.0
Net deferred gain on real estate sale			$ 7.3				$ 39.1
Deferred gain recognized on real estate sale			$ 0.7	$ 2.1	$ 3.4
Leaseback transaction lease period		12 years
Number of building leased \| Building		2	1
Number of vacated buildings \| Building			1
Percentage of management fee included in the base annual rent	3.50%
Lease security deposit	$ 4.7
Letter of credit	$ 3.0
Number of times to renew the lease contract \| RenewalOption			2
Lease extension period			10 years
Rent expense			$ 6.9	$ 5.9	$ 6.0
Amended Lease Term
Leases [Line Items]
Lease expiration date			Dec. 31, 2029
Percentage reduction in base rental	8.00%
Tenant improvement allowances	$ 13.1
Lease security deposit	$ 3.0
Lease Agreement
Leases [Line Items]
Tenant improvement allowances						$ 4.2
Office space area leased \| ft²						44,718
Lease term						10 years 10 months
Lease Agreement \| Letter of Credit
Leases [Line Items]
Lease security deposit						$ 1.0