Derivatives - Schedule of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Jul. 31, 2017
Derivatives, Fair Value [Line Items]
Notional Amount			$ 100,000
Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	$ 1,624,857	$ 1,258,047
Asset	18,728	13,595
Liability	12,400	11,637
Interest rate contracts \| Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	346,545	295,333
Asset	9,073	6,679
Liability	9,073	6,679
Forward commitments \| Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	599,205	474,208
Asset	0	0
Liability	3,327	4,958
Interest rate-lock commitments \| Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	492,507	318,706
Asset	8,121	6,241
Liability	0	0
Futures contracts \| Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	178,000	166,000
Asset	1,456	649
Liability	0	0
Option contracts \| Not designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	8,600	3,800
Asset	78	26
Liability	0	0
Interest rate swaps \| Designated as hedging:
Derivatives, Fair Value [Line Items]
Notional Amount	30,000	30,000
Asset	274	721
Liability	$ 0	$ 0

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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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.

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