Employee Benefits (Narrative Defined Benefit Plans) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 subsidiary
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	2,308
Expected return on plan assets	7.00%
Percentage of investments for long-term growth included in investment strategy	55.00%
Percentage of investments for short-term growth included in investment strategy	45.00%
Discretionary range for pension fund trustee included in investment policy	10.00%
Number of subsidiaries company provides post-retirement healthcare benefits to	2
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	384
Wage Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	349
Salaried Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 0
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	55.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	45.00%
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	80.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	100.00%

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: 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=28361610&loc=d3e1928-114920

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Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

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Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

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Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

-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 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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- Definition

Number of subsidiaries, whose employees meet certain minimum age and service requirements, that are provided post-retirement healthcare benefits by the Company.

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