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Commitments and Contingencies (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Loss Contingencies [Line Items] |  |
Loss Contingency Accrual | $ 8,800 | $ 8,700
Operating Leases, Future Minimum Payments Due, Next Twelve Months | 2,054 |
Operating Leases, Future Minimum Payments, Due in Two Years | 2,744 |
Operating Leases, Future Minimum Payments, Due in Three Years | 2,771 |
Operating Leases, Future Minimum Payments, Due in Four Years | 2,767 |
Operating Leases, Future Minimum Payments, Due in Five Years | 2,761 |
Operating Leases, Future Minimum Payments, Due Thereafter | 68,516 |
Operating Leases, Future Minimum Payments Due | 81,613 |
Net present value adjustment | (48,056) |
Operating Lease, Liability | 33,557 |
Cleven Litigation Case [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Estimate of Possible Loss | 54,600 |
Brown Litigation Case [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Estimate of Possible Loss | $ 8,400 |

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