Income Taxes - Summary of Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2019
Dec. 31, 2018
Deferred tax assets:    
Definite-lived intangibles $ 20,560 $ 18,725
Share-based compensation expense 10,242 9,041
Acquisition-related costs 7,368 4,483
Change in value of consideration payable for acquisition of business 4,366  
Deferred compensation 4,429 3,185
Restructuring expenses 3,256 962
Contingent consideration arrangements 219 248
Goodwill 982 574
Debt issuance costs 1,336  
Unrealized loss on deferred compensation investments 85 536
Loss on equity method investment   283
Other 23 92
Total deferred tax assets 52,866 38,129
Deferred tax liabilities:    
Indefinite-lived intangibles 56,365 41,302
Debt issuance costs   1,101
Depreciation 1,801 1,282
Prepaid expenses 186 161
CEMP base payments interest expense   36
Change in value of consideration payable for acquisition of business   459
Total deferred tax liabilities 58,352 44,341
Net deferred tax asset/(liability) $ (5,486) $ (6,212)