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Income Taxes (Narrative) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Operating Loss Carryforwards [Line Items] |  |  |
Statutory tax rate, percentage | 35.00% | 35.00% | 35.00%
Undistributed earnings of foreign subsidiaries | $ 28,751,000 |  |
Cash held in foreign operations | 26,351,000 |  |
Unrecognized tax benefits that would affect the effective tax rate | 636,000 | $ 859,000 |
Deferred tax assets, net of operating losses | 23,284,000 |  |
Deferred tax assets, net of operating losses | $ 1,737,000 |  |
Minimum |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Statute of limitations expiration period, in years | 4 years |  |
Net operating loss carry forwards, expiration years | Dec. 31, 2016 |  |
Minimum | GERMANY |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Tax examination, years | 2009 |  |
Maximum |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Statute of limitations expiration period, in years | 10 years |  |
Net operating loss carry forwards, expiration years | Dec. 31, 2036 |  |
Maximum | GERMANY |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Tax examination, years | 2012 |  |
RBI |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Unrecognized tax benefits that would affect the effective tax rate | $ 2,830,000 | $ 3,017,000 |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68052875&loc=d3e28680-109314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319 + Details
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