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Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Employee Benefit Plan [Line Items] |  |  |
Defined benefit plan contributions by employer | $ 2,700 | $ 2,600 | $ 1,700
Global Equities |  |  |
Employee Benefit Plan [Line Items] |  |  |
Defined benefit plan, target plan asset allocations | 60.00% |  |
Global Bonds |  |  |
Employee Benefit Plan [Line Items] |  |  |
Defined benefit plan, target plan asset allocations | 18.00% |  |
Alternative Assets |  |  |
Employee Benefit Plan [Line Items] |  |  |
Defined benefit plan, target plan asset allocations | 9.00% |  |
Cash |  |  |
Employee Benefit Plan [Line Items] |  |  |
Defined benefit plan, target plan asset allocations | 13.00% |  |
UNITED KINGDOM |  |  |
Employee Benefit Plan [Line Items] |  |  |
Funding valuation period | 3 years |  |
Defined benefit plan contributions by employer | $ 955 | $ 1,000 |
Defined benefit plan estimated employer contributions for 2014 | $ 1,000 |  |
Defined benefit plans increase future employer contributions percentage | 2.90% |  |

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- Definition The increase in the fair value of plan assets from contributions made by the employer. + 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 (b)(3) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + 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)(i) -URI http://asc.fasb.org/extlink&oid=58740216&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)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + 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=58740216&loc=d3e1928-114920 + Details
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