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Benefit Plans - Additional Information (Detail) | 9 Months Ended
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Sep. 30, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Number of highest-paid consecutive years for benefits | 5 years
Defined Benefit Pension Plan [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Minimum eligibility for full-time employees, age | 21 years
Amount of expected contribution to pension plan in current fiscal year | $ 0
Amount contributed to pension plan | $ 0
Defined Benefit Pension Plan [Member] | Minimum [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Period of service credit by employee | 1 year

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- Definition Defined benefit pension plan minimum eligible age of employee. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Definition Number of highest paid consecutive periods of service for calculation of average compensation related to benefits. + References No definition available. + Details
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Period Type: | duration

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- Definition Period of service credit by employee. + References No definition available. + Details
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Period Type: | duration

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- Definition The increase in the fair value of plan assets from contributions made by the employer. + 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)(3) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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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Period Type: | duration

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- Details
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- Details
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