Fair Value of Financial Assets and Liabilities - Fair Value Hierarchy of Financial Assets and Liabilities under U.S. GAAP Guidance (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets:
Marketable securities	$ 1,031	$ 524,569
Loans held for sale, at fair value	980,859	1,072,479
Debt securities		0
Total assets	1,054,491	1,605,549
Liabilities:
Contingent consideration	12,253	12,338
Total Liabilities	27,503	17,354
Rate lock commitments
Assets:
Derivative asset	5,076	3,957
Liabilities:
Derivative liability	15,250	2,836
Forward sale contracts
Assets:
Derivative asset	67,525	4,544
Liabilities:
Derivative liability		2,180
Level 1
Assets:
Marketable securities	1,031	524,569
Loans held for sale, at fair value	0	0
Debt securities		0
Total assets	1,031	524,569
Liabilities:
Contingent consideration	0	0
Total Liabilities	0	0
Level 1 | Rate lock commitments
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability	0	0
Level 1 | Forward sale contracts
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability		0
Level 2
Assets:
Marketable securities	0	0
Loans held for sale, at fair value	980,859	1,072,479
Debt securities		0
Total assets	980,859	1,072,479
Liabilities:
Contingent consideration	0	0
Total Liabilities	0	0
Level 2 | Rate lock commitments
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability	0	0
Level 2 | Forward sale contracts
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability		0
Level 3
Assets:
Marketable securities	0	0
Loans held for sale, at fair value	0	0
Debt securities		0
Total assets	72,601	8,501
Liabilities:
Contingent consideration	12,253	12,338
Total Liabilities	27,503	17,354
Level 3 | Rate lock commitments
Assets:
Derivative asset	5,076	3,957
Liabilities:
Derivative liability	15,250	2,836
Level 3 | Forward sale contracts
Assets:
Derivative asset	$ 67,525	4,544
Liabilities:
Derivative liability		$ 2,180