Other Investment and Assets - Summary of Other Investments and Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Investments All Other Investments [Abstract]
Cash surrender value of life insurance	$ 19,290	$ 19,142
Workers' compensation insurance security deposits	3,350	3,350
Other	8,728	9,924
Total other investments and assets	$ 31,368	$ 32,416

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

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

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-Name Accounting Standards Codification

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-Section 45

-Paragraph 4

-Subparagraph (d)

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Aggregate carrying amount, as of the balance sheet date, of investments and other noncurrent assets not separately disclosed in the balance sheet due to materiality considerations. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

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

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Current year monetary amount of the change in worker's compensation reserve liability resulting from the discount applied to reduce the reserve to present value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Subparagraph (SX 210.7-03.(a),13(b))

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