Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Allowance for credit losses	$ 158,161	$ 103,267
Share-based compensation expense	15,531	14,233
State income taxes	16,640	16,097
Accrued compensation	44,112	22,578
Lease liability	69,714	60,635
Other accruals	10,018	12,383
Net operating loss	7,501	6,386
Goodwill and intangibles	3,165	3,141
Foreign tax credit carryforward	9,028	0
SBA loan fees	6,115	0
Other	8,110	7,923
Deferred tax assets	348,095	246,643
Valuation allowance	(7,094)	(5,919)
Net deferred tax assets after valuation allowance	341,001	240,724
Deferred tax liabilities:
Derivative equity warrant assets	(71,019)	(45,533)
Net unrealized gains on cash flow hedge derivatives	(49,772)	0
Net unrealized gains on AFS debt securities	(185,634)	(33,480)
Non-marketable and other equity securities	(118,712)	(54,239)
Premises and equipment and other intangibles	(23,721)	(16,459)
Right-of-use asset and deferred rent assets	(52,057)	(50,493)
Other	(12,340)	(12,087)
Deferred tax liabilities	(513,255)	(212,291)
Net deferred tax assets		$ 28,433
Net deferred tax liabilities	$ (172,254)