Fair Value - Level 3 Unobservable Inputs, Mortgage Loans and IRLC (Details) - item	Dec. 31, 2018	Dec. 31, 2017
Mortgage loans held for sale \| Discount rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	2.8	2.9
Mortgage loans held for sale \| Discount rate \| Level 3 \| Maximum
Excess servicing spread financing
Input	9.2	10.0
Mortgage loans held for sale \| Discount rate \| Level 3 \| Weighted average
Excess servicing spread financing
Input	2.9	2.9
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Minimum
Excess servicing spread financing
Input	2.2	3.1
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Maximum
Excess servicing spread financing
Input	5.0	5.6
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Weighted average
Excess servicing spread financing
Input	3.5	3.6
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.1	0.2
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	21.8	72.2
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	20.1	44.6
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.1	0.2
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	40.5	75.2
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	37.7	55.8
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	16.6	25.0
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Maximum
Excess servicing spread financing
Input	100.0	100.0
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Weighted average
Excess servicing spread financing
Input	84.1	85.6
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Minimum
Excess servicing spread financing
Input	1.5	1.4
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Maximum
Excess servicing spread financing
Input	5.5	5.8
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Weighted average
Excess servicing spread financing
Input	3.8	4.0
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.4	0.3
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Maximum
Excess servicing spread financing
Input	3.2	3.0
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Weighted average
Excess servicing spread financing
Input	1.5	1.4
Repurchase agreement derivatives
Excess servicing spread financing
Acceptance rate (as a percent)	97.00%

The repurchase agreement derivatives percentage of approval of mortgage loans financed under the master repurchase agreement.

No definition available.

+ Details

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- Definition

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure loan, held for sale.

+ References

+ Details

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