The amount of servicing asset acquired recognized as of the acquisition date.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Represents the amount of servicing assets that resulted from transfers of financial assets.

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The percentage of loans individually evaluated based on fair value of collateral.

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Fair value portion of Small Business administration servicing assets.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Fair Value - Assets and liabilities measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2022
Fair Value
Percentage of loans individually evaluated based on fair value of collateral	57.00%	57.00%
Fair value assets, level 1 to level 2 transfers amount	$ 0	$ 0	$ 0
Fair value assets, level 2 to level 1 transfers amount	0	0	0
Fair value liabilities, level 1 to level 2 transfers amount	0	0	0
Fair value liabilities, level 2 to level 1 transfers amount	0	0	0
Assets
Derivative financial instruments	209,800	209,800	408,800
Trading securities	31,263	31,263	77,689
Securities available for sale	5,326,822	5,326,822	5,193,478
SBA servicing asset	6,100	6,100
Liabilities
Derivative financial instruments	1,000,000	1,000,000	287,200
Atlantic Capital
Changes in fair value of assets
SBA Servicing asset acquired				$ 3,200
U.S. Treasuries
Assets
Securities available for sale	265,638	265,638
U.S. Government agencies
Assets
Trading securities	11,190	11,190	5,154
Securities available for sale	219,088	219,088	97,117
Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Trading securities			6,853
Securities available for sale	1,698,353	1,698,353	1,831,039
Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Trading securities	4,589	4,589	29,667
Securities available for sale	1,000,398	1,000,398	1,207,241
State and municipal obligations
Assets
Trading securities	13,993	13,993	20,798
Securities available for sale	1,064,852	1,064,852	812,689
Corporate securities.
Assets
Securities available for sale	32,638	32,638	18,734
Significant Other Observable Inputs (Level 2)
Assets
Loans held for sale	28,968	28,968	191,723
Trading securities	31,263	31,263	77,689
Significant Unobservable Inputs (Level 3)
Assets
Mortgage servicing rights	86,610	86,610	65,620
SBA servicing asset	6,068	6,068
Changes in fair value of assets
Changes in hierarchy classifications of Level 3 assets		0
Changes in hierarchy classifications of Level 3 liabilities		0
Recurring basis
Assets
Derivative financial instruments	211,016	211,016	414,742
Loans held for sale	28,968	28,968	191,723
Trading securities	31,263	31,263	77,689
Securities available for sale	5,326,822	5,326,822	5,193,478
Mortgage servicing rights	86,610	86,610	65,620
SBA servicing asset	6,068	6,068
Fair value of Assets, Total	5,690,747	5,690,747	5,943,252
Liabilities
Derivative financial instruments	1,034,143	1,034,143	288,561
Recurring basis \| U.S. Treasuries
Assets
Securities available for sale	265,638	265,638
Recurring basis \| U.S. Government agencies
Assets
Securities available for sale	219,088	219,088
Recurring basis \| Government-sponsored entities debt
Assets
Securities available for sale			97,117
Recurring basis \| Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Securities available for sale	1,698,353	1,698,353	1,831,039
Recurring basis \| Residential Collateralized Mortgage-Obligations Issued By U.S. Government Agencies Or Sponsored Enterprises [Member]
Assets
Securities available for sale	601,045	601,045	725,995
Recurring basis \| Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Securities available for sale	1,000,398	1,000,398	1,207,241
Recurring basis \| State and municipal obligations
Assets
Securities available for sale	1,064,852	1,064,852	812,689
Recurring basis \| Mortgage-backed securities
Assets
Securities available for sale	444,810	444,810	500,663
Recurring basis \| Corporate securities.
Assets
Securities available for sale	32,638	32,638	18,734
Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets
Derivative financial instruments	211,016	211,016	414,742
Loans held for sale	28,968	28,968	191,723
Trading securities	31,263	31,263	77,689
Securities available for sale	5,326,822	5,326,822	5,193,478
Fair value of Assets, Total	5,598,069	5,598,069	5,877,632
Liabilities
Derivative financial instruments	1,034,143	1,034,143	288,561
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. Treasuries
Assets
Securities available for sale	265,638	265,638
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. Government agencies
Assets
Securities available for sale	219,088	219,088
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Government-sponsored entities debt
Assets
Securities available for sale			97,117
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Securities available for sale	1,698,353	1,698,353	1,831,039
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Residential Collateralized Mortgage-Obligations Issued By U.S. Government Agencies Or Sponsored Enterprises [Member]
Assets
Securities available for sale	601,045	601,045	725,995
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises
Assets
Securities available for sale	1,000,398	1,000,398	1,207,241
Recurring basis \| Significant Other Observable Inputs (Level 2) \| State and municipal obligations
Assets
Securities available for sale	1,064,852	1,064,852	812,689
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities
Assets
Securities available for sale	444,810	444,810	500,663
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Corporate securities.
Assets
Securities available for sale	32,638	32,638	18,734
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Mortgage servicing rights	86,610	86,610	65,620
SBA servicing asset	6,068	6,068
Fair value of Assets, Total	92,678	$ 92,678	$ 65,620
Changes in fair value of assets
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax
Unrealized losses included in accumulated other comprehensive (loss) income related to Level 3 financial assets and liabilities		$ 0	$ 0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Mortgage Servicing Rights
Changes in fair value of assets
Fair value of assets at the beginning of the period		65,620	43,820
Servicing assets that resulted from transfers of financial assets		16,002	26,733
Changes in fair value assets due to valuation inputs or assumptions		14,886	4,932
Changes in fair value due to decay		(9,898)	(9,865)
Fair value of assets at the end of the period	86,610	86,610	$ 65,620
Recurring basis \| Significant Unobservable Inputs (Level 3) \| SBA servicing asset
Changes in fair value of assets
Fair value of assets at the beginning of the period	7,369
Servicing assets that resulted from transfers of financial assets	1,273
Changes in fair value assets due to valuation inputs or assumptions	$ (729)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue from Contract with Customer, Excluding Assessed Tax
Changes in fair value due to decay	$ (1,845)
Fair value of assets at the end of the period	$ 6,068	$ 6,068