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Employee Retirement Plans (Narrative) (Details) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2016 USD ($) agreement employee | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | $ 1,377 | $ 1,685 | $ 1,961 | $ 2,179
Net liability | $ 1,573 | $ 1,893 | $ 2,116 |
Number of employees | employee | 2,311 |  |  |
Employees represented by unions through CBAs, percentage | 11.00% |  |  |
Number of CBA's to be negotiated | agreement | 3 |  |  |
Number of CBA's | agreement | 6 |  |  |
Company's maximum contribution percentage | 5.00% |  |  |
National Integrated Group Pension Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
CBAs expiration date | Apr. 30, 2018 |  |  |
Foreign Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | $ 362 |  |  |
Pre-tax accumulated other comprehensive loss - retirement benefit liability adjustment | 91 |  |  |
Net liability | $ 271 |  |  |

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- Definition Before tax amount of additional minimum pension liability not yet recognized as a net periodic pension cost. + 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 (j) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 + Details
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- Definition The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. + 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 (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 + Details
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- Definition Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan, in CCYY-MM-DD format. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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