Employee Benefit Plans (Matching Retirement/Savings Plan) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Contribution Pension and Other Postretirement Plans Disclosure [Line Items]
Employer matching contribution percentage	50.00%
Percentage of pay deferred by employee eligible for employer matching contributions	6.00%
Matching and discretionary contributions	$ 0.7	$ 0.6	$ 0.5
COB Matching Retirement/Savings Plan [Member]
Defined Contribution Pension and Other Postretirement Plans Disclosure [Line Items]
Employer matching contribution percentage	50.00%
Percentage of pay deferred by employee eligible for employer matching contributions	6.00%
Matching and discretionary contributions	$ 0.7	$ 0.6	$ 0.5

Defined Contribution Pension and Other Postretirement Plans Disclosure [Line Items]

No definition available.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ 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

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Details

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