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

No definition available.

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- Definition

Amount of expense (reversal of expense) in connection with exit or disposal activity (including executory costs such as maintenance charges) net of estimated income from potential subleasing.

+ References

No definition available.

+ Details

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- Definition

The date of expiration of the sublease agreement between the entity and a third party, in CCYY-MM format.

+ References

No definition available.

+ Details

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- Definition

The year of expiration of the initial lease term.

+ References

No definition available.

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- Definition

Lease extension period.

+ 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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Balance Type:	debit
Period Type:	instant

- Definition

Number of buildings leased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

The number of sublease agreements related to real estate properties.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

The total area (square footage) of the subleased property.

+ References

No definition available.

+ Details

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Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying amount of mortgage loans on real estate that were sold during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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Balance Type:	credit
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- Definition

The total amount of sublease rental income recognized during the period that reduces the entity's rent expense incurred under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77907795&loc=d3e50609-112754

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51843-112757

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-Topic 840
-SubTopic 40
-Section 55
-Paragraph 51
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51840-112757

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
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-Paragraph 51
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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- Details

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Real Estate - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended			12 Months Ended
Real Estate - Additional Information (Detail) $ in Millions	Dec. 31, 2007 USD ($) Building	Mar. 31, 2018 USD ($) ft² RenewalOption Lease_Agreements	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2008 USD ($)
Real Estate Properties [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
Leaseback transaction lease period	12 years
Number of building leased \| Building	2
Net deferred gain on real estate sale		$ 8.6				$ 39.1
Deferred gain recognized on real estate sale		$ 0.2		$ 0.9
Lease expiration year		2029
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
Subleased agreement area \| ft²		16,000
Rental income from sublease agreement		$ 0.3
Sublease
Real Estate Properties [Line Items]
Number of sublease agreements \| Lease_Agreements		1
Reversal of cease use expense			$ 0.5
Second Sublease
Real Estate Properties [Line Items]
Lease expiration date		2018-03
Amended Lease Term
Real Estate Properties [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