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Retirement Plans (Narrative) (Details) - Pension Plan $ in Thousands | 3 Months Ended
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Mar. 31, 2018 USD ($) plan
Defined Benefit Plan Disclosure |
Defined contribution plan, number | 6
United States |
Defined Benefit Plan Disclosure |
Number of retirement plans | 3
Defined benefit plan, number | 1
Defined contribution plan, number | 2
Canada |
Defined Benefit Plan Disclosure |
Post-retirement benefit plan number | 1
Defined contribution plan, number | 2
United Kingdom |
Defined Benefit Plan Disclosure |
Defined benefit plan, number | 1
Defined contribution plan, number | 2
Defined benefit plans, estimated future employer contributions in current fiscal year | $ | $ 262
Defined benefit plan, contributions by employer | $ | $ 65

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- Definition Number of defined contribution plans offered by the company. + References No definition available. + Details
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- Definition Number of retirement plans offered by the company. + References No definition available. + Details
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- Definition Number of post-retirement benefit plans offered by the company. + References No definition available. + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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