Loans Receivable, Including Loans Held For Sale - Loans Receivable (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Receivable [Line Items]
Financing receivable, including loans held for sale, gross, total	$ 2,560,225		$ 554,722
Financing receivable, ratio to total, including loans held for sale (as a percent)	100.00%		100.00%
Financing receivable, gross, current	$ 309,569		$ 358,577
Financing receivable, gross, non-current	2,250,656		196,145
Allowance for loan losses, total	(58,960)		(36,682)
Allowance for loan losses, current	(58,960)		(36,682)
Allowance for loan losses, non-current	0		0
Total loans receivable, net	2,501,265		518,040
Loans receivable, net, current	250,609		321,895
Loans receivable, net, noncurrent	2,250,656		196,145
Loans receivable, including loans held for sale, current	321,987		546,908
Loans receivable, including loans held for sale, non-current	2,250,656		196,145
Pledged as collateral	6,387		15,737
Increase in loans held for sale	6,768,053	$ 11,296,371
Financing Receivable, after Allowance for Credit Loss	2,560,225		554,722
Other borrowings	2,032,236		0
Loan Modifications, COVID-19
Receivable [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 31,143
Financing Receivable, Number Of Short-Term Deferments \| loan	11,380
Financing Receivable, after Allowance for Credit Loss, Percentage	1.25%
Small Business Administration (SBA), CARES Act, Paycheck Protection Program
Receivable [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 2,096,006
Other borrowings	2,032,236
Loans held for sale
Receivable [Line Items]
Financing receivable, including loans held for sale, gross, total	$ 71,378		$ 225,013
Financing receivable, ratio to total, including loans held for sale (as a percent)
Financing receivable, gross, current	$ 71,378		$ 225,013
Financing receivable, gross, non-current	0		0
Commercial real estate loans
Receivable [Line Items]
Financing receivable, including loans held for sale, gross, total	$ 617		$ 659
Financing receivable, ratio to total, including loans held for sale (as a percent)	0.00%		0.00%
Financing receivable, gross, current	$ 0		$ 0
Financing receivable, gross, non-current	617		659
Commercial and industrial
Receivable [Line Items]
Financing receivable, including loans held for sale, gross, total	$ 2,347,005		$ 251,349
Financing receivable, ratio to total, including loans held for sale (as a percent)	92.00%		45.00%
Financing receivable, gross, current	$ 238,359		$ 233,510
Financing receivable, gross, non-current	2,108,646		17,839
Consumer loans
Receivable [Line Items]
Financing receivable, including loans held for sale, gross, total	$ 212,603		$ 302,714
Financing receivable, ratio to total, including loans held for sale (as a percent)	8.00%		55.00%
Financing receivable, gross, current	$ 71,210		$ 125,067
Financing receivable, gross, non-current	141,393		177,647
Allowance for loan losses, total	(37,028)		(25,738)
Financing Receivable, after Allowance for Credit Loss	212,603		302,714
WebBank
Receivable [Line Items]
Servicing asset	2,858		$ 2,898
Proceeds from loans held for sale	6,919,881	$ 11,306,443
Financing Receivable, Allowance for Credit Losses, Period Increase (Decrease)	$ 6,539
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease), Percentage	12.00%

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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