Business and Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Allowance for Doubtful Accounts Receivable [Roll Forward] | |||
| Beginning Balance | $ 35,690 | $ 34,861 | $ 27,401 |
| Accounts Written Off, net of Recoveries | (192,133) | (167,094) | (155,651) |
| Accounts Receivable Provision | 203,389 | 167,923 | 163,111 |
| Ending Balance | $ 46,946 | $ 35,690 | $ 34,861 |
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- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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