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Business Combinations - Pro Forma Financial Information (Details) - DNB - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |
Total Revenue |  | $ 341,117 | $ 325,668
Net Income | [1] | $ 120,964 | $ 116,046
Basic (in usd per share) | [1] | $ 3.03 | $ 2.90
Diluted (in usd per share) | [1] | $ 3.03 | $ 2.88
Merger-related expenses |  | $ 13,600 |
[1] | Excludes non-recurring merger-related expenses of $13.6 million, net of tax at 21 percent.

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