Commitments and Contingencies - Schedule of Future Minimum Rental Payments under Non-Cancellable Operating Leases (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Operating Leased Assets [Line Items]
2015	$ 250
2016	3,084
2017	826
2018	42
2019	26
Thereafter	793
Total	5,021
Operating Leases [Member]
Operating Leased Assets [Line Items]
2015	13,169
2016	12,899
2017	12,448
2018	13,516
2019	12,490
Thereafter	117,608
Total minimum lease payments	$ 182,130

Undiscounted amount of the accrual for environmental loss contingencies.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q1)

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-Number Topic 5

-Section Y

-Paragraph Question 1

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

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-Section 50

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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-Paragraph 2

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