Significant Accounting Policies and Basis of Presentation - Schedule of Error Correction on Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Loans held for sale	$ 1,383	$ 146,077
Loans receivable, mortgage warehouse, at fair value	1,516,327	1,793,408
Total loans receivable, net of allowance for loan losses	$ 8,715,536	8,523,651
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Loans held for sale		1,939,485
Loans receivable, mortgage warehouse, at fair value		0
Total loans receivable, net of allowance for loan losses		6,730,243
Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Loans held for sale		(1,793,408)
Loans receivable, mortgage warehouse, at fair value		1,793,408
Total loans receivable, net of allowance for loan losses		$ 1,793,408

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

+ References

No definition available.

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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Amount before allowance of revolving credit lines for to originate and purchase financial assets including, but not limited to, mortgage loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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