Employee Benefit Plans (Employe Savings and Stock Ownership Plan - 401k Plan) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans
Compensation expense	$ 0.4	$ 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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- 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

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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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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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Balance Type:	debit
Period Type:	duration