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Benefit Plans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Mar. 31, 2013 | Sep. 30, 2013 Age
Defined Benefit Plan Disclosure [Line Items] |  |
Recorded gain from termination of post retirement benefit liability |  | $ 543
Pension Plan, Defined Benefit [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Minimum eligibility for full-time employees, age |  | 21
Period of service credit by employee |  | 1 year
Amount contributed to pension plan, Expected in future |  | 500
Amount of contributed made to pension plan | $ 500 |

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- Definition Defined benefit pension plan minimum eligible age of employee. + References No definition available. + Details
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- Definition Period of service credit by employee. + References No definition available. + Details
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- Definition The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Details
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- Definition Changes in the defined benefit obligation, not otherwise separately disclosed in the financial statements. + References No definition available. + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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