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Employee Benefits - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Dec. 31, 2015
Retirement Benefits [Abstract] |  |
Pension plan curtailment gain | $ 1.0 |
Period of unrecognized benefits associated with prior year plan amendments that would have been amortized into income | 7 years |
Number of consecutive years of employee's compensation |  | 5 years
Number of total years of employee's compensation |  | 10 years
Expected long-term rate of return on plan assets |  | 7.50%

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- Definition Defined Benefit Plan, Unrecognized Benefits Due to Settlements and Curtailments, Period of Recognition + References No definition available. + Details
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- Definition Number Of Consecutive Periods Of Highest Compensation Used To Determine Defined Benefit Pension Plan Benefits + References No definition available. + Details
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- Definition Number Of Periods Used To Determine Defined Benefit Pension Plan Benefits + References No definition available. + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + 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 (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from settlement and curtailment. + 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 (h)(7) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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