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Commitments and Contingencies (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) property | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Operating Leases |  |  |
2017 | $ 19,458 |  |
2018 | 17,719 |  |
2019 | 14,200 |  |
2020 | 11,660 |  |
2021 | 9,084 |  |
Thereafter | 10,742 |  |
Total | 82,863 |  |
Related Party |  |  |
2017 | 1,169 |  |
2018 | 1,302 |  |
2019 | 1,282 |  |
2020 | 1,314 |  |
2021 | 1,347 |  |
Thereafter | 3,999 |  |
Total | 10,413 |  |
Purchase Obligation, Due in Next Twelve Months | 8,694 |  |
Purchase Obligation, Due in Second Year | 4,121 |  |
Purchase Obligation, Due in Third Year | 1,255 |  |
Purchase Obligation, Due in Fourth Year | 0 |  |
Purchase Obligation, Due in Fifth Year | 0 |  |
Purchase Obligation, Due after Fifth Year | 0 |  |
Purchase Obligation | 14,070 |  |
Total |  |  |
2017 | 29,321 |  |
2018 | 23,142 |  |
2019 | 16,737 |  |
2020 | 12,974 |  |
2021 | 10,431 |  |
Thereafter | 14,741 |  |
Total | 107,346 |  |
Deferred Rent Credit, Current | 600 | $ 500 |
Deferred rent liability, noncurrent | 5,200 | 4,300 |
Rent expense | 25,600 | 21,600 | $ 17,600
Costs and Expenses, Related Party | 1,300 | 1,300 | $ 1,300
Self Insurance Reserve | 1,800 | 1,800 |
Workerscompensationreceivable | 14,001 | 13,238 |
Letters of credit outstanding | $ 4,000 | $ 3,500 |
Apex Systems |  |  |
Total |  |  |
Number of leased properties owned by related parties (in number of properties) | property | 2 |  |

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