Summary of Significant Accounting Policies - Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 156,654us-gaap_PropertyPlantAndEquipmentGross	$ 148,440us-gaap_PropertyPlantAndEquipmentGross
Less Accumulated Depreciation	(53,503)	(47,058)
Property plant and equipment net excluding capitalized cost	103,151	101,382
Construction In Progress	5,477us-gaap_ConstructionInProgressGross	3,805us-gaap_ConstructionInProgressGross
Property, Plant and Equipment, net	108,628us-gaap_PropertyPlantAndEquipmentNet	105,187us-gaap_PropertyPlantAndEquipmentNet
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	38,455	37,354
Estimated useful life	Indefinite
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	39,715	39,068
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	21,486	21,151
Estimated useful life	30 years
Furniture, Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	32,544	30,761
Machinery and Service Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 24,454	$ 20,106
Minimum [Member] \| Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	20 years
Minimum [Member] \| Furniture, Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Minimum [Member] \| Machinery and Service Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Maximum [Member] \| Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	50 years
Maximum [Member] \| Furniture, Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Maximum [Member] \| Machinery and Service Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	20 years

Property plant and equipment net excluding capitalized cost.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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- Definition

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

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-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Name Accounting Standards Codification

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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