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Deposits Deposits (Tables) | 12 Months Ended
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Dec. 31, 2018
Statement of Financial Position [Abstract] |
Deposit Asset, Type [Table Text Block] | Deposits consisted of the following:
| December 31,
(in thousands) | 2018 |  | 2017
Deposits – health insurance | $ | 6,200 |  |  | $ | 5,300 |
Deposits – workers’ compensation | 166,474 |  |  | 154,215 |
Deposits | $ | 172,674 |  |  | $ | 159,515 |

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration