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Employee Pension Plans | 12 Months Ended
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Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract] |
Employee Pension Plans | (8) Employee Pension Plans Forrester sponsors several defined contribution plans for eligible employees. Generally, the defined contribution plans have funding provisions which, in certain situations, require contributions based upon formulas relating to employee wages or the level of elective participant contributions, as well as allow for additional discretionary contributions. Further, certain plans contain vesting provisions. Forrester’s contributions to these plans totaled approximately $5.2 million, $4.3 million and $4.1 million for the years ended December 31, 2017, 2016 and 2015, respectively.

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- Definition The entire disclosure for pension and other postretirement benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017 + Details
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