Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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A narrative description of investment policies and strategies, including target allocation percentages or range of percentages considering the major categories of plan assets as of the latest statement of financial position presented (on a weighted-average basis for employers with more than one plan), and other factors that are pertinent to an understanding of those policies and strategies such as investment goals, risk management practices, allowable and prohibited investment types including the use of derivatives, diversification, and the relationship between plan assets and benefit obligations. For investment funds disclosed as major categories, the narrative description would be expected to also include a description of the significant investment strategies of those funds.

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This element represents the information provided by management related to the valuation techniques used to develop the fair value measurements of plan assets as of the date of the statement of financial position.

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Retirement Plans (Information About Plan Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	$ 25	$ 51,223
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Policies and Strategies Narrative Description	Plan assets consist primarily of various fixed income and equity investments. The Company's primary investment objective is to provide long-term growth of capital while accepting a moderate level of risk. The investments are limited to cash and equivalents, bonds, preferred stocks, and common stocks. The investment target ranges and actual allocation of pension plan assets by major category at December 31, 2014 and 2013 are as follows
Defined Benefit Plan, Actual Plan Asset Allocations	100.00%	100.00%
Defined Benefit Plan, Plan Assets at Fair Value, Valuation Techniques	In accordance with the fair value disclosure requirements with FASB ASC 820, "Fair Value Measurements and Disclosures," the following assets were measured at fair value on a recurring basis at December 31, 2014 and 2013. Additional information regarding FASB ASC 820 and the fair value hierarchy can be found in Note 19, Fair Value Measurements
Fair value of plan assets	15,205	15,039	13,262
United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Policies and Strategies Narrative Description	Plan assets are invested by the trustees in accordance with a written statement of investment principles. This statement permits investment in equities, corporate bonds, United Kingdom government securities, commercial property, and cash, based on certain target allocation percentages. Asset allocation is primarily based on a strategy to provide steady growth without undue fluctuations. The target asset allocation percentages for 2014 are as follows:
Fair value of plan assets	6,757	6,769	6,051
Cash and Cash Equivalents [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Cash and cash equivalents
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	10.00%
Defined Benefit Plan, Actual Plan Asset Allocations	2.00%	4.00%
Fair value of plan assets	347	568
Cash and Cash Equivalents [Member] \| United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Cash
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	100.00%
Fair value of plan assets	218	369
Fixed Income Funds [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Total fixed income funds
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	25.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	50.00%
Defined Benefit Plan, Actual Plan Asset Allocations	34.00%	27.00%
Fair value of plan assets	5,194	4,005
Municipal Bonds [Member] \| United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	U.K. Government securities
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	50.00%
Fair value of plan assets	1,899	1,468
Corporate Bond Securities [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,194	4,005
Equity Funds [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Total mutual funds and equities
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	50.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	70.00%
Defined Benefit Plan, Actual Plan Asset Allocations	64.00%	69.00%
Fair value of plan assets	9,664	10,466
Equity Funds [Member] \| United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Equity securities
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	100.00%
Fair value of plan assets	2,156	2,803
Mutual Funds [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,566	9,142
Asset Allocations, Common Stock [Member] \| United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,098	1,324
Commercial Property [Member] \| United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Investment Strategies, Investment Fund Category	Commercial property
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	50.00%
Fair value of plan assets	$ 2,484	$ 2,129