Bank segment - Allowance for credit losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Allowance for credit losses:
Beginning balance	$ 101,201	$ 53,355
Charge-offs	(3,681)	(6,631)
Recoveries	1,308	1,018
Provision	(7,035)	9,901
Ending balance	91,793	77,084
Real estate \| Residential 1-4 family
Allowance for credit losses:
Beginning balance	4,600	2,380
Charge-offs	0	0
Recoveries	3	53
Provision	658	(107)
Ending balance	5,261	4,476
Real estate \| Commercial real estate
Allowance for credit losses:
Beginning balance	35,607	15,053
Charge-offs	0	0
Recoveries	0	0
Provision	(1,262)	1,326
Ending balance	34,345	16,587
Real estate \| Home equity line of credit
Allowance for credit losses:
Beginning balance	6,813	6,922
Charge-offs	(50)	0
Recoveries	15	6
Provision	(877)	(162)
Ending balance	5,901	6,225
Real estate \| Residential land
Allowance for credit losses:
Beginning balance	609	449
Charge-offs	0	(8)
Recoveries	10	9
Provision	(46)	(34)
Ending balance	573	352
Real estate \| Commercial construction
Allowance for credit losses:
Beginning balance	4,149	2,097
Charge-offs	0	0
Recoveries	0	0
Provision	(2,696)	1,060
Ending balance	1,453	3,446
Real estate \| Residential construction
Allowance for credit losses:
Beginning balance	11	3
Charge-offs	0	0
Recoveries	0	0
Provision	5	(3)
Ending balance	16	14
Commercial
Allowance for credit losses:
Beginning balance	25,462	10,245
Charge-offs	(771)	(369)
Recoveries	273	186
Provision	(460)	1,993
Ending balance	24,504	12,977
Consumer
Allowance for credit losses:
Beginning balance	23,950	16,206
Charge-offs	(2,860)	(6,254)
Recoveries	1,007	764
Provision	(2,357)	5,828
Ending balance	$ 19,740	33,007
Impact of adoption of ASU No. 2016-13
Allowance for credit losses:
Beginning balance		19,441
Impact of adoption of ASU No. 2016-13 \| Real estate \| Residential 1-4 family
Allowance for credit losses:
Beginning balance		2,150
Impact of adoption of ASU No. 2016-13 \| Real estate \| Commercial real estate
Allowance for credit losses:
Beginning balance		208
Impact of adoption of ASU No. 2016-13 \| Real estate \| Home equity line of credit
Allowance for credit losses:
Beginning balance		(541)
Impact of adoption of ASU No. 2016-13 \| Real estate \| Residential land
Allowance for credit losses:
Beginning balance		(64)
Impact of adoption of ASU No. 2016-13 \| Real estate \| Commercial construction
Allowance for credit losses:
Beginning balance		289
Impact of adoption of ASU No. 2016-13 \| Real estate \| Residential construction
Allowance for credit losses:
Beginning balance		14
Impact of adoption of ASU No. 2016-13 \| Commercial
Allowance for credit losses:
Beginning balance		922
Impact of adoption of ASU No. 2016-13 \| Consumer
Allowance for credit losses:
Beginning balance		$ 16,463

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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