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Retirement Plans (Information About Plan Assets) (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
UNITED STATES |  |  |
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 cash equivalents, bonds, preferred stocks, and common stocks. The investment target ranges and actual allocation of pension plan assets by major category at December 31, 2016 and 2015 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 of FASB ASC 820, "Fair Value Measurements and Disclosures," the following assets were measured at fair value on a recurring basis at December 31, 2016 and 2015. Additional information regarding FASB ASC 820 and the fair value hierarchy can be found in Note 18 Fair Value Measurements |  |
Fair value of plan assets | $ 14,180 | $ 14,235 | $ 15,205
UNITED STATES | Cash and Cash Equivalents [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 | 5.00% | 9.00% |
Fair value of plan assets | $ 660 | $ 1,248 |
UNITED STATES | Fixed Income Funds [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 | 33.00% | 35.00% |
Fair value of plan assets | $ 4,767 | $ 4,926 |
UNITED STATES | Corporate Bond Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 4,767 | $ 4,926 |
UNITED STATES | Equity Funds [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 | 62.00% | 56.00% |
Fair value of plan assets | $ 8,753 | $ 8,061 |
UNITED STATES | Mutual Funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 8,753 | 8,061 |
UNITED STATES | Asset Allocations, Common Stock [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 0 |  |
UNITED KINGDOM |  |  |
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 2016 are as follows: |  |
Fair value of plan assets | $ 5,826 | 6,661 | $ 6,757
UNITED KINGDOM | Cash and Cash Equivalents [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 | $ 707 | 242 |
UNITED KINGDOM | Municipal Bonds [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 | $ 1,347 | 1,301 |
UNITED KINGDOM | Equity Funds [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 | $ 2,617 | 2,656 |
UNITED KINGDOM | Commercial Property [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 | $ 1,155 | $ 2,462 |

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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6749337 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6520858 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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