Loans - Recorded investment in past due loans by loan segment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	$ 1,911,174	$ 1,664,039
Nonaccrual	461	581
Totals	1,912,038	1,664,931
30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due	403	311
Commercial
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	276,028	260,813
Nonaccrual	7	8
Totals	276,035	260,833
Commercial \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due		12
Construction and Land Development
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	196,600	209,843
Nonaccrual	176	198
Totals	196,776	210,041
HELOC and 1-4 Family Junior Mortgage
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	28,621	30,939
Nonaccrual		317
Totals	28,621	31,256
1st REM - 1-4 Family
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	36,671	37,705
Totals	36,671	37,905
1st REM - 1-4 Family \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due		200
LOCs and 2nd REM - Rentals
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	18,527	12,443
Nonaccrual	144
Totals	18,671	12,443
1st REM - Rentals
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	176,114	145,169
Nonaccrual	134
Totals	176,648	145,169
1st REM - Rentals \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due	400
Multifamily
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	515,014	407,934
Totals	515,014	407,934
CRE Owner Occupied
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	66,584	64,360
Totals	66,584	64,458
CRE Owner Occupied \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due		98
CRE Non-owner Occupied
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	592,545	490,632
Totals	592,545	490,632
Consumer and other
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, Current	4,470	4,201
Nonaccrual		58
Totals	4,473	4,260
Consumer and other \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Accruing Interest, past due	$ 3	$ 1

Amount of financing receivable not past due.

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Amount of financing receivable on nonaccrual status.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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