Employee Benefit Plans (Details 2) (Qualified Pension Plan, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Employee Benefits Plans
Fair value of plan assets	124,372	$ 120,604
Funded pension plan assets, by asset category (as a percent)	100.00%	100.00%
Minimum
Employee Benefits Plans
Period to meet policy goals	3 years
Maximum
Employee Benefits Plans
Period to meet policy goals	5 years
Quoted Prices in Active Markets for Identical Assets (Level 1)
Employee Benefits Plans
Fair value of plan assets	114,391	116,066
Significant Other Observable Inputs (Level 2)
Employee Benefits Plans
Fair value of plan assets	9,982	4,538
Equity Securities
Employee Benefits Plans
Fair value of plan assets	82,010	85,606
Funded pension plan assets, by asset category (as a percent)	66.00%	71.00%
Equity Securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Employee Benefits Plans
Fair value of plan assets	82,010	85,606
Debt Securities
Employee Benefits Plans
Fair value of plan assets	32,381	30,460
Funded pension plan assets, by asset category (as a percent)	26.00%	25.00%
Debt Securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Employee Benefits Plans
Fair value of plan assets	32,381	30,460
Other Securities
Employee Benefits Plans
Fair value of plan assets	9,981	4,538
Funded pension plan assets, by asset category (as a percent)	8.00%	4.00%
Other Securities \| Significant Other Observable Inputs (Level 2)
Employee Benefits Plans
Fair value of plan assets	9,982	$ 4,538

Represents the defined benefit plan period required to meet investment policy's goal.

No definition available.

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- Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of 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)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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