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Acquisitions - Summary of Pre-tax Merger Related Costs (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |
Business Combination, Acquisition Related Costs, Legal Fees | $ 0.3 | $ 0.5 |
Business Combination, Acquisition Related Costs, Employee Expense | 0.6 | 0.1 |
Business Combination, Acquisition Related Costs, Technology and Contract Termination | 0.8 | 1.5 |
Business Combination, Acquisition Related Costs, Other Expenses | 0.6 | 0.2 |
Acquisition related expenses | $ 2.3 | $ 2.3 | $ 2.3

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- Definition Business Combination, Acquisition Related Costs, Technology and Contract Termination + References No definition available. + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
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