Carrying Value of Acquired Impaired Loans [Roll Forward]

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Reductions for repayments foreclosures and decreases in fair value

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Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Fair value at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of cash flows expected to be collected at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of contractually required payments receivable at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans accounted for as debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Loans and Leases (Changes In Carrying Value Of Acquired Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 01, 2018	Oct. 02, 2018	May 01, 2018	May 05, 2017	Jan. 13, 2017	Dec. 31, 2015
Carrying Value of Acquired Impaired Loans [Roll Forward]
Reductions for repayments, foreclosures and changes in carrying value, net of accretion	$ (248,114)	$ (322,447)	$ (298,602)
Outstanding principal balance	960,457	1,175,441	1,266,395
PCI Loans	606,576	762,998	809,169						$ 950,516
PCI loans	30,190	199,682	80,690
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Accretion	61,502	76,594	$ 76,565
Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI Loans	296,672	393,419
PCI Loans
Loans and Leases Receivable Disclosure [Abstract]
Nonaccruing	$ 1,300	$ 624
Palmetto Heritage Bancshares
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition							$ 4,783
Carrying Value of Acquired Impaired Loans [Roll Forward]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition							4,112
PCI loans				$ 3,863			3,863
Palmetto Heritage Bancshares \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				1,637
Palmetto Heritage Bancshares \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				2,226
Palmetto Heritage Bancshares \| Construction and land development \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				212
Palmetto Heritage Bancshares \| Construction and land development \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				0
Palmetto Heritage Bancshares \| Mortgage \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				1,053
Palmetto Heritage Bancshares \| Mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				2,226
Palmetto Heritage Bancshares \| Revolving mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				0
Palmetto Heritage Bancshares \| Other commercial real estate \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				0
Palmetto Heritage Bancshares \| Commercial and industrial \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				372
Palmetto Heritage Bancshares \| Consumer \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans				$ 0
Capital Commerce Bancorp
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition							13,871
Carrying Value of Acquired Impaired Loans [Roll Forward]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition							11,814
PCI loans					$ 10,772		10,772
Capital Commerce Bancorp \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					4,250
Capital Commerce Bancorp \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					6,522
Capital Commerce Bancorp \| Construction and land development \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					1,482
Capital Commerce Bancorp \| Construction and land development \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					0
Capital Commerce Bancorp \| Mortgage \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					1,846
Capital Commerce Bancorp \| Mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					6,503
Capital Commerce Bancorp \| Revolving mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					0
Capital Commerce Bancorp \| Other commercial real estate \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					0
Capital Commerce Bancorp \| Commercial and industrial \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					922
Capital Commerce Bancorp \| Consumer \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans					$ 19
HomeBancorp Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition							26,651
Carrying Value of Acquired Impaired Loans [Roll Forward]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition							19,697
PCI loans						$ 15,555	15,555
HomeBancorp Inc. \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						8,238
HomeBancorp Inc. \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						7,317
HomeBancorp Inc. \| Construction and land development \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						0
HomeBancorp Inc. \| Construction and land development \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						0
HomeBancorp Inc. \| Mortgage \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						7,815
HomeBancorp Inc. \| Mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						7,317
HomeBancorp Inc. \| Revolving mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						0
HomeBancorp Inc. \| Other commercial real estate \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						0
HomeBancorp Inc. \| Commercial and industrial \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						423
HomeBancorp Inc. \| Consumer \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans						$ 0
Guaranty Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition							158,456
Carrying Value of Acquired Impaired Loans [Roll Forward]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition							142,000
PCI loans							114,533
Guaranty Bank \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							701
Guaranty Bank \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							113,832
Guaranty Bank \| Construction and land development \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							55
Guaranty Bank \| Construction and land development \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							26
Guaranty Bank \| Mortgage \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							644
Guaranty Bank \| Mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							80,475
Guaranty Bank \| Revolving mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							33,319
Guaranty Bank \| Other commercial real estate \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							0
Guaranty Bank \| Commercial and industrial \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							2
Guaranty Bank \| Consumer \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans							$ 12
Harvest Community Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition								$ 111,250
Carrying Value of Acquired Impaired Loans [Roll Forward]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition								101,802
PCI loans								85,149
Harvest Community Bank \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								54,976
Harvest Community Bank \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								30,173
Harvest Community Bank \| Construction and land development \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								7,061
Harvest Community Bank \| Construction and land development \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								0
Harvest Community Bank \| Mortgage \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								21,836
Harvest Community Bank \| Mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								25,857
Harvest Community Bank \| Revolving mortgage \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								3,434
Harvest Community Bank \| Other commercial real estate \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								6,404
Harvest Community Bank \| Commercial and industrial \| Commercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								19,675
Harvest Community Bank \| Consumer \| Noncommercial
Carrying Value of Acquired Impaired Loans [Roll Forward]
PCI loans								$ 882