Fair Value Measurements - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial Assets:
Equity investments without readily determinable fair values	$ 38,100	$ 31,037
Financial Liabilities:
Investment securities held to maturity, at amortized cost	271,066	0
Investment securities held to maturity, fair value	258,407	0
Level 1 | Carrying Amount
Financial Assets:
Cash and cash equivalents	506,776	316,266
Financial Liabilities:
Convertible notes, net	217,148	216,209
Level 1 | Estimated Fair Value
Financial Assets:
Cash and cash equivalents	506,776	316,266
Financial Liabilities:
Convertible notes, net	213,937	214,612
Level 2/3 | Carrying Amount
Financial Assets:
Accrued interest receivable	55,460	41,842
Level 2/3 | Estimated Fair Value
Financial Assets:
Accrued interest receivable	55,460	41,842
Level 2 | Carrying Amount
Financial Assets:
Interest bearing deposits in other financial institutions	735	12,851
Equity investments without readily determinable fair values	38,093
Loans held for sale	49,245	99,049
Customers’ liabilities on acceptances	818	1,521
Financial Liabilities:
Noninterest bearing deposits	4,849,493	5,751,870
Saving and other interest bearing demand deposits	5,899,248	6,500,227
Time deposits	4,990,060	2,788,353
FHLB and FRB borrowings, Fair Value Disclosure	865,000
FHLB and FRB borrowings		300,000
Subordinated debentures	106,565	105,354
Accrued interest payable	26,668	4,272
Acceptances outstanding	818	1,521
Level 2 | Estimated Fair Value
Financial Assets:
Interest bearing deposits in other financial institutions	733	12,853
Equity investments without readily determinable fair values	38,093	31,037
Loans held for sale	49,248	103,767
Customers’ liabilities on acceptances	818	1,521
Financial Liabilities:
Noninterest bearing deposits	4,849,493	5,751,870
Saving and other interest bearing demand deposits	5,899,248	6,500,227
Time deposits	5,020,093	2,790,596
FHLB and FRB borrowings, Fair Value Disclosure	867,088
FHLB and FRB borrowings		301,936
Subordinated debentures	107,944	117,961
Accrued interest payable	26,668	4,272
Acceptances outstanding	818	1,521
Level 3 | Carrying Amount
Financial Assets:
Loans receivable, net	15,241,181	13,812,193
Servicing assets, net	11,628	10,418
Level 3 | Estimated Fair Value
Financial Assets:
Loans receivable, net	14,745,881	13,698,579
Servicing assets, net	$ 17,375	$ 13,500