Borrowings (Long-Term Obligations) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Long-term Debt, Fiscal Year Maturity [Abstract]
2019	$ 61,995
2020	13,332
2021	114,138
2022	125,500
2023	6,526
Thereafter	267,147
Total long-term obligations	588,638	$ 319,867
Trust Preferred Securities	128,500	118,500
Junior Subordinated Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	132,500	122,200
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 1.75% maturing June 30, 2036
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 88,145	88,145
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 1.75% maturing June 30, 2036 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Description of variable rate basis	3-month LIBOR
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.25% maturing June 15, 2034
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 19,588	19,588
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.25% maturing June 15, 2034 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Description of variable rate basis	3-month LIBOR
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.85% maturing April 7, 2034
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 10,310	10,310
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.85% maturing April 7, 2034 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.85%
Description of variable rate basis	3-month LIBOR
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.00% maturing July 7, 2036
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 0	4,124
Junior Subordinated Debt [Member] \| Junior subordinated debenture at 3-month LIBOR plus 2.00% maturing July 7, 2036 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Description of variable rate basis	3-month LIBOR
Junior Subordinated Debt [Member] \| Junior subordinated debentures at 3-month LIBOR plus 2.80% maturing March 30, 2034
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 14,433	$ 0
Junior Subordinated Debt [Member] \| Junior subordinated debentures at 3-month LIBOR plus 2.80% maturing March 30, 2034 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.80%
Description of variable rate basis	3-month LIBOR
Junior Subordinated Debt [Member] \| Junior subordinated debentures at 7.00% maturing December 31, 2026 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Debt interest rate		7.00%
Junior Subordinated Debt [Member] \| Junior subordinated debentures at 6.50% maturing October 1, 2025 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Debt interest rate		6.50%
Junior Subordinated Debt [Member] \| Junior subordinated debentures at 7.13% maturing February 25, 2025 \| Libor 3 Month Rate [Member]
Debt Instrument [Line Items]
Debt interest rate		7.13%
Capital Lease Obligations [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 8,230	$ 13,160
Notes payable to FHLB of Atlanta \| Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 3.17% and maturing through March 2032
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	317,191	$ 165,205
Notes payable to FHLB of Atlanta \| Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 3.17% and maturing through March 2032 \| Minimum
Debt Instrument [Line Items]
Debt interest rate		0.75%
Notes payable to FHLB of Atlanta \| Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 3.17% and maturing through March 2032 \| Maximum
Debt Instrument [Line Items]
Debt interest rate		3.17%
Subordinated Debt [Member] \| Junior subordinated debentures at 7.00% maturing December 31, 2026
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	20,000	$ 20,000
Subordinated Debt [Member] \| Junior subordinated debentures at 6.50% maturing October 1, 2025
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	7,500	0
Subordinated Debt [Member] \| Junior subordinated debentures at 7.13% maturing February 25, 2025
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	5,000	0
Unamortized Purchase Accounting Adjustments [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	(1,569)	(1,426)
Other Long Term Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	3,385	761
Unsecured Term Loan [Member] \| Unsecured term loan at 1-month LIBOR plus 1.10% maturing September 5, 2022
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 96,425	0
Unsecured Term Loan [Member] \| Unsecured term loan at 1-month LIBOR plus 1.10% maturing September 5, 2022 \| Libor 1 Month Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.10%
Biscayne Bancshares And HomeBancorp [Member] \| Subordinated Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 32,500	$ 20,000

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