Employee Benefit Plans (Employe Savings and Stock Ownership Plan - 401k Plan) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans
Compensation expense	$ 0.3	$ 0.3	$ 0.3
Defined Contribution Plan, Maximum Annual Contribution Per Employee (as a percentage)	20.00%
Defined Contribution Plan, Employer Matching Contribution (as a percentage)	25.00%
Maximum Percentage of Employee's Salary Eligible for Defined Contribution Plan (as a percentage)	7.00%

Maximum Percentage of Employee's Salary Eligible for Defined Contribution Plan

No definition available.

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- Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amount of plan compensation cost recognized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 40

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

+ Details

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