REGULATORY CAPITAL REQUIREMENTS AND RESTRICTIONS ON SUBSIDIARY DIVIDENDS (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 2,204,829	$ 2,040,500
Actual - Ratio	0.1476	0.1590
For Capital Adequacy Purposes - Amount	$ 1,194,970	$ 1,026,345
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 1,763,990	$ 1,590,111
Actual - Ratio	0.1181	0.1239
For Capital Adequacy Purposes - Amount	$ 896,228	$ 769,759
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 1,653,285	$ 1,479,406
Actual - Ratio	11.07%	11.53%
For Capital Adequacy Purposes - Amount	$ 672,171	$ 577,319
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 1,763,990	$ 1,590,111
Actual - Ratio	0.0913	0.0857
For Capital Adequacy Purposes - Amount	$ 772,911	$ 742,155
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
Minimum Capital Requirement
Tier 1 Capital (to Average Assets)
Retained earnings available for dividend payments	$ 702,200
Capital Requirement to Remain Well Capitalized
Tier 1 Capital (to Average Assets)
Retained earnings available for dividend payments	403,900
HTLF Bank
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 824,069
Actual - Ratio	0.1172
For Capital Adequacy Purposes - Amount	$ 562,497
For Capital Adequacy Purposes - Ratio	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 703,122
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000
Dubuque Bank and Trust Company
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 184,096	$ 180,934
Actual - Ratio	0.1301	0.1307
For Capital Adequacy Purposes - Amount	$ 113,197	$ 110,758
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 141,497	$ 138,447
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 174,684	$ 168,321
Actual - Ratio	0.1235	0.1216
For Capital Adequacy Purposes - Amount	$ 84,898	$ 83,068
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 113,197	$ 110,758
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 174,684	$ 168,321
Actual - Ratio	12.35%	12.16%
For Capital Adequacy Purposes - Amount	$ 63,674	$ 62,301
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 91,973	$ 89,991
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 174,684	$ 168,321
Actual - Ratio	0.0808	0.0802
For Capital Adequacy Purposes - Amount	$ 86,473	$ 83,982
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 108,091	$ 104,978
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
Illinois Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount		$ 135,986
Actual - Ratio		0.1288
For Capital Adequacy Purposes - Amount		$ 84,466
For Capital Adequacy Purposes - Ratio		0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount		$ 105,583
To Be Well Capitalized Under Prompt Corrective Action - Ratio		0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount		$ 126,869
Actual - Ratio		0.1202
For Capital Adequacy Purposes - Amount		$ 63,350
For Capital Adequacy Purposes - Ratio		0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 84,466
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount		$ 126,869
Actual - Ratio		12.02%
For Capital Adequacy Purposes - Amount		$ 47,512
For Capital Adequacy Purposes - Ratio		4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 68,629
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount		$ 126,869
Actual - Ratio		0.0755
For Capital Adequacy Purposes - Amount		$ 67,212
For Capital Adequacy Purposes - Ratio		0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 84,016
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0500
Wisconsin Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 128,490	$ 124,009
Actual - Ratio	0.1312	0.1427
For Capital Adequacy Purposes - Amount	$ 78,336	$ 69,499
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 97,920	$ 86,874
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 119,231	$ 114,825
Actual - Ratio	0.1218	0.1322
For Capital Adequacy Purposes - Amount	$ 58,752	$ 52,124
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 78,336	$ 69,499
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 119,231	$ 114,825
Actual - Ratio	12.18%	13.22%
For Capital Adequacy Purposes - Amount	$ 44,064	$ 39,093
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 63,648	$ 56,468
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 119,231	$ 114,825
Actual - Ratio	0.0922	0.0966
For Capital Adequacy Purposes - Amount	$ 51,753	$ 47,551
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 64,691	$ 59,439
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
New Mexico Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 238,190	$ 213,981
Actual - Ratio	0.1323	0.1210
For Capital Adequacy Purposes - Amount	$ 144,059	$ 141,530
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 180,073	$ 176,912
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 223,602	$ 198,728
Actual - Ratio	0.1242	0.1123
For Capital Adequacy Purposes - Amount	$ 108,044	$ 106,147
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 144,059	$ 141,530
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 223,602	$ 198,728
Actual - Ratio	12.42%	11.23%
For Capital Adequacy Purposes - Amount	$ 81,033	$ 79,611
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 117,048	$ 114,993
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 223,602	$ 198,728
Actual - Ratio	0.0812	0.0778
For Capital Adequacy Purposes - Amount	$ 110,214	$ 102,173
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 137,767	$ 127,716
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
Arizona Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount		$ 157,475
Actual - Ratio		0.1261
For Capital Adequacy Purposes - Amount		$ 99,886
For Capital Adequacy Purposes - Ratio		0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount		$ 124,858
To Be Well Capitalized Under Prompt Corrective Action - Ratio		0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount		$ 147,098
Actual - Ratio		0.1178
For Capital Adequacy Purposes - Amount		$ 74,915
For Capital Adequacy Purposes - Ratio		0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 99,886
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount		$ 147,098
Actual - Ratio		11.78%
For Capital Adequacy Purposes - Amount		$ 56,186
For Capital Adequacy Purposes - Ratio		4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 81,158
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount		$ 147,098
Actual - Ratio		0.0799
For Capital Adequacy Purposes - Amount		$ 73,605
For Capital Adequacy Purposes - Ratio		0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 92,006
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0500
Rocky Mountain Bank
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 69,792	$ 64,366
Actual - Ratio	0.1284	0.1307
For Capital Adequacy Purposes - Amount	$ 43,489	$ 39,385
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 54,361	$ 49,231
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 63,814	$ 59,159
Actual - Ratio	0.1174	0.1202
For Capital Adequacy Purposes - Amount	$ 32,617	$ 29,538
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 43,489	$ 39,385
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 63,814	$ 59,159
Actual - Ratio	11.74%	12.02%
For Capital Adequacy Purposes - Amount	$ 24,463	$ 22,154
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 35,335	$ 32,000
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 63,814	$ 59,159
Actual - Ratio	0.0849	0.0827
For Capital Adequacy Purposes - Amount	$ 30,064	$ 28,614
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 37,580	$ 35,767
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
Citywide Banks
Total Capital (to Risk-Weighted Assets)
Actual - Amount		$ 265,964
Actual - Ratio		0.1509
For Capital Adequacy Purposes - Amount		$ 140,999
For Capital Adequacy Purposes - Ratio		0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount		$ 176,248
To Be Well Capitalized Under Prompt Corrective Action - Ratio		0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 762,103	$ 244,722
Actual - Ratio	0.1084	0.1389
For Capital Adequacy Purposes - Amount	$ 421,873	$ 105,749
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 562,497	$ 140,999
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 762,103	$ 244,722
Actual - Ratio	10.84%	13.89%
For Capital Adequacy Purposes - Amount	$ 316,405	$ 79,312
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 457,029	$ 114,561
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 762,103	$ 244,722
Actual - Ratio	0.0864	0.0954
For Capital Adequacy Purposes - Amount	$ 352,914	$ 102,587
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 441,143	$ 128,233
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
Minnesota Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount		$ 87,263
Actual - Ratio		0.1479
For Capital Adequacy Purposes - Amount		$ 47,194
For Capital Adequacy Purposes - Ratio		0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount		$ 58,993
To Be Well Capitalized Under Prompt Corrective Action - Ratio		0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount		$ 81,637
Actual - Ratio		0.1384
For Capital Adequacy Purposes - Amount		$ 35,396
For Capital Adequacy Purposes - Ratio		0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 47,194
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount		$ 81,637
Actual - Ratio		13.84%
For Capital Adequacy Purposes - Amount		$ 26,547
For Capital Adequacy Purposes - Ratio		4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 38,346
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount		$ 81,637
Actual - Ratio		0.0969
For Capital Adequacy Purposes - Amount		$ 33,698
For Capital Adequacy Purposes - Ratio		0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 42,123
Bank of Blue Valley
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 162,131	$ 160,694
Actual - Ratio	0.1607	0.1674
For Capital Adequacy Purposes - Amount	$ 80,689	$ 76,785
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 100,861	$ 95,982
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 155,002	$ 150,305
Actual - Ratio	0.1537	0.1566
For Capital Adequacy Purposes - Amount	$ 60,516	$ 57,589
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 80,689	$ 76,785
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 155,002	$ 150,305
Actual - Ratio	15.37%	15.66%
For Capital Adequacy Purposes - Amount	$ 45,387	$ 43,192
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 65,560	$ 62,388
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 155,002	$ 150,305
Actual - Ratio	0.1075	0.1075
For Capital Adequacy Purposes - Amount	$ 57,676	$ 55,921
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 72,095	$ 69,901
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500
Premier Valley Bank
Total Capital (to Risk-Weighted Assets)
Actual - Amount		$ 111,741
Actual - Ratio		0.1282
For Capital Adequacy Purposes - Amount		$ 69,720
For Capital Adequacy Purposes - Ratio		0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount		$ 87,151
To Be Well Capitalized Under Prompt Corrective Action - Ratio		0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount		$ 104,336
Actual - Ratio		0.1197
For Capital Adequacy Purposes - Amount		$ 52,290
For Capital Adequacy Purposes - Ratio		0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 69,720
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount		$ 104,336
Actual - Ratio		11.97%
For Capital Adequacy Purposes - Amount		$ 39,218
For Capital Adequacy Purposes - Ratio		4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 56,648
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount		$ 104,336
Actual - Ratio		0.0922
For Capital Adequacy Purposes - Amount		$ 45,256
For Capital Adequacy Purposes - Ratio		0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount		$ 56,570
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio		0.0500
First Bank & Trust
Total Capital (to Risk-Weighted Assets)
Actual - Amount	$ 288,518	$ 282,231
Actual - Ratio	0.1351	0.1548
For Capital Adequacy Purposes - Amount	$ 170,835	$ 145,823
For Capital Adequacy Purposes - Ratio	0.0800	0.0800
To Be Well Capitalized Under Prompt Corrective Action - Amount	$ 213,543	$ 182,279
To Be Well Capitalized Under Prompt Corrective Action - Ratio	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets)
Actual - Amount	$ 267,169	$ 263,096
Actual - Ratio	0.1251	0.1443
For Capital Adequacy Purposes - Amount	$ 128,126	$ 109,367
For Capital Adequacy Purposes - Ratio	0.0600	0.0600
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 170,835	$ 145,823
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0800	0.0800
Common Equity Tier 1 (to Risk-Weighted Assets)
Actual - Amount	$ 267,169	$ 263,096
Actual - Ratio	12.51%	11.43%
For Capital Adequacy Purposes - Amount	$ 96,094	$ 82,025
For Capital Adequacy Purposes - Ratio	4.50%	4.50%
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 138,803	$ 118,481
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	6.50%	6.50%
Tier 1 Capital (to Average Assets)
Actual - Amount	$ 267,169	$ 263,096
Actual - Ratio	0.0929	0.0984
For Capital Adequacy Purposes - Amount	$ 115,026	$ 106,986
For Capital Adequacy Purposes - Ratio	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions - Amount	$ 143,782	$ 133,732
To Be Well Capitalized Under Prompt Corrective Action Provisions - Ratio	0.0500	0.0500