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Accounts Receivable (Tables) | 12 Months Ended
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Dec. 31, 2018
Accounts Receivable Additional Disclosures [Abstract] |
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] | Accounts receivable, net consisted of the following:
| December 31,
(in thousands) | 2018 |  | 2017
Trade | $ | 10,015 |  |  | $ | 12,292 |
Unbilled | 385,567 |  |  | 318,431 |
Other | 5,041 |  |  | 3,258 |
Accounts receivable, net | $ | 400,623 |  |  | $ | 333,981 |
Unbilled accounts receivable | Client prepayments directly attributable to unbilled accounts receivable have been netted against such receivables as the gross billings have been earned and the payroll cost has been incurred, thus we have the legal right of offset for these amounts. Unbilled accounts receivable consisted of the following:
| December 31,
(in thousands) | 2018 |  | 2017
Accrued worksite employee payroll cost | $ | 329,979 |  |  | $ | 267,402 |
Unbilled revenues | 89,765 |  |  | 74,632 |
Customer prepayments | (34,177 | ) |  | (23,603 | )
Unbilled accounts receivable | $ | 385,567 |  |  | $ | 318,431 |

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- Definition Tabular disclosure of the various types of accounts receivable, including trade, unbilled and other, and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References No definition available. + Details
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- References No definition available. + Details
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- Definition Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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