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Leases - Operating Lease Costs (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Operating Lease Cost |  |  |  |
Operating lease expense | $ 3,803 | $ 3,945 | $ 13,280 | $ 10,394
Sublease Income | 143 | 0 | 143 | 0
Compensation and benefits |  |  |  |
Operating Lease Cost |  |  |  |
Operating lease expense | 128 | 117 | 388 | 350
Occupancy |  |  |  |
Operating Lease Cost |  |  |  |
Operating lease expense | 3,736 | 3,739 | 12,801 | 9,793
Communication and technology |  |  |  |
Operating Lease Cost |  |  |  |
Operating lease expense | $ 82 | $ 89 | 234 | $ 251
Abandonment of leased office space | Occupancy |  |  |  |
Operating Lease Cost |  |  |  |
Operating lease expense |  |  | $ 1,500 |

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- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
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- Definition Amount of sublease income excluding finance and operating lease expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details
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