Commitments and Contingencies - Aircraft Sale-Leaseback (Details) - Garden City lease - USD ($) $ in Millions	Oct. 03, 2003	May 31, 2018	May 31, 2017
Aircraft Sale-Leaseback Transactions
Proceeds from sale-leaseback	$ 14.0
Cost of the facility	9.5
Accumulated depreciation of the facility	4.6
Deferred gain realized on the sale	$ 9.1
Deferred gain amortization period	20 years
Unamortized balance of the deferred gain		$ 2.5	$ 2.9

Represents the term of lease over which the deferred gain realized on the sale of the facility is amortized.

No definition available.

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- Definition

The accumulated depreciation and amortization related to the asset(s) sold in connection with the property sold to another party and leased back to the seller.

+ 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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-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51840-112757

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- Definition

The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 25
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-URI http://asc.fasb.org/extlink&oid=77913853&loc=d3e49567-112750

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The historical cost of the asset(s) sold in connection with the sale of the property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
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-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51831-112757

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-Publisher FASB
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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.

+ References

No definition available.

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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 investing activities.

+ References

+ Details

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