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Acquisitions (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Business Acquisitions [Abstract] |  |  |
Goodwill acquired | $ 0 | $ 6,726 |
Retirement Plan Services, LLC [Member] |  |  |
Business Acquisitions [Abstract] |  |  |
Total consideration paid |  | 13,000 |
Goodwill acquired |  | 6,700 |
Contingent consideration, liability |  | $ 5,100 |
Downeast Pension Services, Inc.[Member] |  |  |
Business Acquisitions [Abstract] |  |  |
Total consideration paid |  |  | $ 5,700
Goodwill acquired |  |  | 2,600
Contingent consideration, liability |  |  | $ 1,700

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
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