Nature Of Operations And Summary Of Significant Accounting Policies (Detail) - Interest Costs (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest costs charged to expense	$ 816us-gaap_InterestAndDebtExpense	$ 1,118us-gaap_InterestAndDebtExpense
Plus: Interest cost capitalized	107us-gaap_InterestCostsCapitalized	108us-gaap_InterestCostsCapitalized
Total	$ 923us-gaap_InterestCostsIncurred	$ 1,226us-gaap_InterestCostsIncurred

Interest and debt related expenses associated with nonoperating financing activities of the entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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Period Type:	duration

- Definition

Amount of interest capitalized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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- Definition

Total interest costs incurred during the period and either capitalized or charged against earnings.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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