Subsequent Events - Additional Information (Detail) (Subsequent Event, USD $) In Millions, unless otherwise specified	0 Months Ended
Apr. 16, 2015 renewal_option	Apr. 16, 2015
Subsequent Event [Line Items]
Number of renewal terms	2
Lease extension term	5 years
Payments due in 2015	$ 0.4	$ 0.4
Payments due in 2016	4	4
Payments due in 2017	6	6
Payments due 2026	2
Minimum
Subsequent Event [Line Items]
Payments due in 2018-2025	7
Maximum
Subsequent Event [Line Items]
Payments due in 2018-2025	$ 9

Lessee Leasing Arrangements, Operating Leases, Number of Renewal Term

No definition available.

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- Definition

Operating Leases, Future Minimum Payments Due, Annual, Thereafter

+ References

No definition available.

+ Details

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- Definition

Operating Leases, Future Minimum Payments Due, Annual, Years Four to Eleven

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: 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=6584154&loc=d3e38371-112697

+ Details

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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