Retirement Benefit Plans (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Retirement Benefit Plans [Abstract]
Net acuarial losses related to supplemental retirement plans	$ 482	$ 373
Supplemental executive retirement plans recognized liabilities	3,969	3,882
Net actuarial loss for retirement plan, amortized from accumulated other comprehensive income into net periodic benefit cost	38
Total expense for 401(k) plan	$ 375	$ 356	$ 321

Defined benefit plan, actuarial gain loss related to supplemental retirement plans.

No definition available.

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- Definition

Defined Benefit Plan Supplemental Executive Retirement Plans Recognized Liabilities

+ References

No definition available.

+ Details

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- Definition

Amount included in accumulated other comprehensive income (AOCI) 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, including gain (loss), prior service cost (credit), and transition asset (obligation).

+ References

No definition available.

+ Details

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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=6414718&loc=d3e28014-114942

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- Details

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