Accumulated Other Comprehensive Income/(Loss)  | 
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| Accumulated Other Comprehensive Income/(Loss) [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Accumulated Other Comprehensive Income/(Loss) | 
 Note L — Accumulated Other Comprehensive Income/(Loss) The change in unrealized gains and losses, net of applicable taxes, related to investments in available-for-sale securities and foreign currency translation adjustments are the primary components reported in accumulated other comprehensive income/(loss) in the Company’s Consolidated Balance Sheets. The changes in accumulated other comprehensive income/(loss) are as follows:   
  Reclassification adjustments out of accumulated other comprehensive income/(loss) are for realized gains and losses on the sale of available-for-sale securities and are reflected in interest on funds held for clients and interest (expense)/income on the Consolidated Statements of Income and Comprehensive Income.  
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