Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets, Net - Summary of Intangible Assets (Detail)

v3.20.2
Intangible Assets, Net - Summary of Intangible Assets (Detail) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Cost of intangible assets gross, beginning balance     $ 46,527 $ 25,027 $ 25,027
Disposal     (6)    
Cost of intangible assets gross, ending balance $ 46,521   46,521   46,527
Accumulated amortization, beginning balance     (17,241) (15,134) (15,134)
Amortization expense (664) $ (705) (2,069) (1,401) (2,107)
Disposal     5    
Accumulated amortization, ending balance (19,305)   (19,305)   (17,241)
Net book value 27,216   $ 27,216   29,286
Minimum          
Useful lives     3 years    
Maximum          
Useful lives     20 years    
Cortina Asset Management, LLC          
Acquisition of Cortina         21,500
Customer Relationships          
Cost of intangible assets gross, beginning balance     $ 44,060 22,560 22,560
Cost of intangible assets gross, ending balance 44,060   44,060   44,060
Accumulated amortization, beginning balance     (14,833) (12,887) (12,887)
Amortization expense     (2,011)   (1,946)
Accumulated amortization, ending balance (16,844)   (16,844)   (14,833)
Net book value 27,216   $ 27,216   $ 29,227
Customer Relationships | Minimum          
Useful lives     10 years   10 years
Customer Relationships | Maximum          
Useful lives     20 years   20 years
Customer Relationships | Cortina Asset Management, LLC          
Acquisition of Cortina         $ 21,500
Other Intangible Assets          
Cost of intangible assets gross, beginning balance     $ 2,467 2,467 2,467
Disposal     (6)    
Cost of intangible assets gross, ending balance 2,461   2,461   2,467
Accumulated amortization, beginning balance     (2,408) $ (2,247) (2,247)
Amortization expense     (58)   (161)
Disposal     5    
Accumulated amortization, ending balance $ (2,461)   $ (2,461)   (2,408)
Net book value         $ 59
Other Intangible Assets | Minimum          
Useful lives     3 years   3 years
Other Intangible Assets | Maximum          
Useful lives     5 years   5 years