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Other Assets - Additional Information (Detail) (USD $)
3 Months Ended 12 Months Ended
Sep. 30, 2012
Dec. 31, 2013
Dec. 31, 2012
Long Lived Assets Held For Sale [Line Items]      
Assets held for sale write-down     $ 1,162,000us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf
Proceeds from sale of assets-held-for-sale   1,559,000us-gaap_ProceedsFromSaleOfPropertyHeldForSale 3,555,000us-gaap_ProceedsFromSaleOfPropertyHeldForSale
CompX      
Long Lived Assets Held For Sale [Line Items]      
Assets held for sale write-down 400,000us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf
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Proceeds from sale of assets-held-for-sale   1,600,000us-gaap_ProceedsFromSaleOfPropertyHeldForSale
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3,600,000us-gaap_ProceedsFromSaleOfPropertyHeldForSale
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Gain (Loss) on sale of facility     $ (800,000)us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges
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