Loans, Changes in the Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2020		Mar. 31, 2019	Dec. 31, 2019	Mar. 31, 2020		Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 201,371
Balance at end of period				$ 201,371
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	21,907
Provision for loan losses	15,500
Balance at end of period	56,276			21,907
Allowance for credit losses on loans
Provision for credit losses	53,001		$ 6,000
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	201,371		238,023	238,023
Charge offs				(74,313)
Recoveries				19,161
Net Charge offs				(55,152)
Provision for loan losses				18,500
Balance at end of period	337,793	[1]		201,371
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							$ 16,165
Collectively evaluated							185,205
Total allowance for loan losses	201,371		238,023	201,371	$ 337,793	[1]	201,371
Loans [Abstract]
Individually evaluated							110,043
Collectively evaluated							22,709,845
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							1,552
Loans and Leases Receivable, Net of Deferred Income, Total					24,365,633		22,821,440
First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	179
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	91,133		108,835	108,835
Charge offs				(63,315)
Recoveries				11,875
Net Charge offs				(51,441)
Provision for loan losses				33,738
Balance at end of period				91,133
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							12,010
Collectively evaluated							79,123
Total allowance for loan losses	91,133		108,835	91,133			91,133
Loans [Abstract]
Individually evaluated							62,035
Collectively evaluated							7,292,217
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							342
Loans and Leases Receivable, Net of Deferred Income, Total					8,517,974		7,354,594
Commercial real estate — owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	10,284		9,255	9,255
Charge offs				(222)
Recoveries				2,795
Net Charge offs				2,573
Provision for loan losses				(1,543)
Balance at end of period				10,284
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							19
Collectively evaluated							10,265
Total allowance for loan losses	10,284		9,255	10,284			10,284
Loans [Abstract]
Individually evaluated							1,676
Collectively evaluated							909,010
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							579
Loans and Leases Receivable, Net of Deferred Income, Total					940,687		911,265
Commercial and business lending
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	101,417		118,090	118,090
Charge offs				(63,537)
Recoveries				14,670
Net Charge offs				(48,868)
Provision for loan losses				32,195
Balance at end of period				101,417
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							12,029
Collectively evaluated							89,388
Total allowance for loan losses	101,417		118,090	101,417			101,417
Loans [Abstract]
Individually evaluated							63,711
Collectively evaluated							8,201,227
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							921
Loans and Leases Receivable, Net of Deferred Income, Total					9,458,661		8,265,858
Commercial real estate — investor
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	40,514		40,844	40,844
Charge offs				0
Recoveries				31
Net Charge offs				31
Provision for loan losses				(361)
Balance at end of period				40,514
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							15
Collectively evaluated							40,498
Total allowance for loan losses	40,514		40,844	40,514			40,514
Loans [Abstract]
Individually evaluated							4,633
Collectively evaluated							3,789,755
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							129
Loans and Leases Receivable, Net of Deferred Income, Total					4,038,036		3,794,517
Real estate construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	24,915		28,240	28,240
Charge offs				(60)
Recoveries				302
Net Charge offs				243
Provision for loan losses				(3,568)
Balance at end of period				24,915
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							67
Collectively evaluated							24,848
Total allowance for loan losses	24,915		28,240	24,915			24,915
Loans [Abstract]
Individually evaluated							477
Collectively evaluated							1,420,416
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							7
Loans and Leases Receivable, Net of Deferred Income, Total					1,544,858		1,420,900
Commercial real estate lending
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	65,429		69,084	69,084
Charge offs				(60)
Recoveries				333
Net Charge offs				274
Provision for loan losses				(3,929)
Balance at end of period				65,429
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							82
Collectively evaluated							65,346
Total allowance for loan losses	65,429		69,084	65,429			65,429
Loans [Abstract]
Individually evaluated							5,110
Collectively evaluated							5,210,171
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							136
Loans and Leases Receivable, Net of Deferred Income, Total					5,582,894		5,215,417
Total commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	166,846		187,174	187,174
Charge offs				(63,597)
Recoveries				15,003
Net Charge offs				(48,594)
Provision for loan losses				28,266
Balance at end of period				166,846
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							12,111
Collectively evaluated							154,734
Total allowance for loan losses	166,846		187,174	166,846			166,846
Loans [Abstract]
Individually evaluated							68,821
Collectively evaluated							13,411,398
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							1,057
Loans and Leases Receivable, Net of Deferred Income, Total					15,041,555		13,481,275
Residential mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	16,960		25,595	25,595
Charge offs				(3,322)
Recoveries				692
Net Charge offs				(2,630)
Provision for loan losses				(6,005)
Balance at end of period				16,960
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							2,740
Collectively evaluated							14,220
Total allowance for loan losses	16,960		25,595	16,960			16,960
Loans [Abstract]
Individually evaluated							35,554
Collectively evaluated							8,100,958
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							469
Loans and Leases Receivable, Net of Deferred Income, Total							8,136,980
Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	10,926		19,266	19,266
Charge offs				(1,846)
Recoveries				2,599
Net Charge offs				753
Provision for loan losses				(9,093)
Balance at end of period				10,926
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							1,190
Collectively evaluated							9,737
Total allowance for loan losses	10,926		19,266	10,926			10,926
Loans [Abstract]
Individually evaluated							4,422
Collectively evaluated							847,577
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							26
Loans and Leases Receivable, Net of Deferred Income, Total					844,901		852,025
Other consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	6,639		5,988	5,988
Charge offs				(5,548)
Recoveries				868
Net Charge offs				(4,681)
Provision for loan losses				5,332
Balance at end of period				6,639
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							125
Collectively evaluated							6,514
Total allowance for loan losses	6,639		5,988	6,639			6,639
Loans [Abstract]
Individually evaluated							1,247
Collectively evaluated							349,912
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							0
Loans and Leases Receivable, Net of Deferred Income, Total							351,159
Total consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	34,525		50,849	50,849
Charge offs				(10,716)
Recoveries				4,159
Net Charge offs				(6,558)
Provision for loan losses				(9,766)
Balance at end of period				34,525
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually evaluated							4,055
Collectively evaluated							30,471
Total allowance for loan losses	34,525		$ 50,849	34,525			34,525
Loans [Abstract]
Individually evaluated							41,223
Collectively evaluated							9,298,447
Financing Receivable Acquired and Accounted under Modification of Impaired Loans							495
Loans and Leases Receivable, Net of Deferred Income, Total					$ 9,324,079		$ 9,340,164
Allowance for Loan Losses [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	201,371
Jan. 1, 2020	313,828
Charge offs	(19,308)
Recoveries	2,268
Net Charge offs	(17,040)
Allowance for PCD loans for bank acquisition	3,504
Provision for loan losses	34,957
Balance at end of period	337,793			201,371
Allowance for credit losses on loans
Charge offs	(19,308)
Recoveries	2,268
Net Charge offs	17,040
Allowance for PCD loans for bank acquisition	3,504
Allowance for Loan Losses [Member] | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	2,543
Allowance for Loan Losses [Member] | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	112,457
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	112,457
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	112,457
Allowance for Loan Losses [Member] | Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	91,133
Jan. 1, 2020	144,052
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	(15,049)
Allowance for PCD loans for bank acquisition	293
Provision for loan losses	44,284
Balance at end of period	173,988			91,133
Allowance for credit losses on loans
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	15,049
Allowance for PCD loans for bank acquisition	293
Allowance for Loan Losses [Member] | Commercial and industrial | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	408
Allowance for Loan Losses [Member] | Commercial and industrial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	52,919
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	52,919
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	52,919
Allowance for Loan Losses [Member] | Commercial real estate — owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	10,284
Jan. 1, 2020	8,433
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	890
Provision for loan losses	734
Balance at end of period	10,313			10,284
Allowance for credit losses on loans
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	890
Allowance for Loan Losses [Member] | Commercial real estate — owner occupied | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	255
Allowance for Loan Losses [Member] | Commercial real estate — owner occupied | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Allowance for Loan Losses [Member] | Commercial and business lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	101,417
Jan. 1, 2020	152,485
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	(15,048)
Allowance for PCD loans for bank acquisition	1,183
Provision for loan losses	45,018
Balance at end of period	184,301			101,417
Allowance for credit losses on loans
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	15,048
Allowance for PCD loans for bank acquisition	1,183
Allowance for Loan Losses [Member] | Commercial and business lending | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	663
Allowance for Loan Losses [Member] | Commercial and business lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	51,068
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	51,068
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	51,068
Allowance for Loan Losses [Member] | Commercial real estate — investor
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	40,514
Jan. 1, 2020	42,555
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	753
Provision for loan losses	(1,664)
Balance at end of period	42,115			40,514
Allowance for credit losses on loans
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	753
Allowance for Loan Losses [Member] | Commercial real estate — investor | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	472
Allowance for Loan Losses [Member] | Commercial real estate — investor | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,041
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,041
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	2,041
Allowance for Loan Losses [Member] | Real estate construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	24,915
Jan. 1, 2020	32,382
Charge offs	(7)
Recoveries	19
Net Charge offs	(11)
Allowance for PCD loans for bank acquisition	435
Provision for loan losses	(2,573)
Balance at end of period	30,746			24,915
Allowance for credit losses on loans
Charge offs	(7)
Recoveries	19
Net Charge offs	11
Allowance for PCD loans for bank acquisition	435
Allowance for Loan Losses [Member] | Real estate construction | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	492
Allowance for Loan Losses [Member] | Real estate construction | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	7,467
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	7,467
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	7,467
Allowance for Loan Losses [Member] | Commercial real estate lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	65,428
Jan. 1, 2020	74,937
Charge offs	(7)
Recoveries	19
Net Charge offs	(11)
Allowance for PCD loans for bank acquisition	1,188
Provision for loan losses	(4,237)
Balance at end of period	72,861			65,428
Allowance for credit losses on loans
Charge offs	(7)
Recoveries	19
Net Charge offs	11
Allowance for PCD loans for bank acquisition	1,188
Allowance for Loan Losses [Member] | Commercial real estate lending | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	964
Allowance for Loan Losses [Member] | Commercial real estate lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	9,508
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	9,508
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	9,508
Allowance for Loan Losses [Member] | Total commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	166,846
Jan. 1, 2020	227,422
Charge offs	(16,343)
Recoveries	1,307
Net Charge offs	(15,037)
Allowance for PCD loans for bank acquisition	2,371
Provision for loan losses	40,781
Balance at end of period	257,162			166,846
Allowance for credit losses on loans
Charge offs	(16,343)
Recoveries	1,307
Net Charge offs	15,037
Allowance for PCD loans for bank acquisition	2,371
Allowance for Loan Losses [Member] | Total commercial | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	1,627
Allowance for Loan Losses [Member] | Total commercial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	60,576
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	60,576
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	60,576
Allowance for Loan Losses [Member] | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	16,960
Jan. 1, 2020	50,175
Charge offs	(1,003)
Recoveries	91
Net Charge offs	(912)
Allowance for PCD loans for bank acquisition	651
Provision for loan losses	(6,370)
Balance at end of period	43,947			16,960
Allowance for credit losses on loans
Charge offs	(1,003)
Recoveries	91
Net Charge offs	912
Allowance for PCD loans for bank acquisition	651
Allowance for Loan Losses [Member] | Residential mortgage | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	403
Allowance for Loan Losses [Member] | Residential mortgage | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Allowance for Loan Losses [Member] | Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	10,926
Jan. 1, 2020	22,575
Charge offs	(526)
Recoveries	598
Net Charge offs	(71)
Allowance for PCD loans for bank acquisition	422
Provision for loan losses	(1,135)
Balance at end of period	22,308			10,926
Allowance for credit losses on loans
Charge offs	(526)
Recoveries	598
Net Charge offs	71
Allowance for PCD loans for bank acquisition	422
Allowance for Loan Losses [Member] | Home equity | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	374
Allowance for Loan Losses [Member] | Home equity | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	11,649
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	11,649
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	11,649
Allowance for Loan Losses [Member] | Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	6,639
Jan. 1, 2020	13,655
Charge offs	(1,434)
Recoveries	272
Net Charge offs	(1,162)
Allowance for PCD loans for bank acquisition	61
Provision for loan losses	1,681
Balance at end of period	14,376			6,639
Allowance for credit losses on loans
Charge offs	(1,434)
Recoveries	272
Net Charge offs	1,162
Allowance for PCD loans for bank acquisition	61
Allowance for Loan Losses [Member] | Other consumer | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	140
Allowance for Loan Losses [Member] | Other consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	7,016
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	7,016
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	7,016
Allowance for Loan Losses [Member] | Total consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	34,525
Jan. 1, 2020	86,405
Charge offs	(2,963)
Recoveries	961
Net Charge offs	(2,003)
Allowance for PCD loans for bank acquisition	1,134
Provision for loan losses	(5,824)
Balance at end of period	80,631			34,525
Allowance for credit losses on loans
Charge offs	(2,963)
Recoveries	961
Net Charge offs	2,003
Allowance for PCD loans for bank acquisition	1,134
Allowance for Loan Losses [Member] | Total consumer | First Staunton Bancshares [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision for loan losses	917
Allowance for Loan Losses [Member] | Total consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	51,880
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	51,880
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	51,880
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	21,907
Jan. 1, 2020	40,597
Provision for loan losses	15,500
Balance at end of period	56,276			21,907
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	179
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,690
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,690
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	18,690
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and industrial
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	12,276
Jan. 1, 2020	8,278
Provision for loan losses	6,461
Balance at end of period	14,800			12,276
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and industrial | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	61
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and industrial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — owner occupied
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	127
Jan. 1, 2020	127
Provision for loan losses	109
Balance at end of period	240			127
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — owner occupied | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	4
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — owner occupied | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	0
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	0
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and business lending
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	12,403
Jan. 1, 2020	8,405
Provision for loan losses	6,570
Balance at end of period	15,040			12,403
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and business lending | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	65
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial and business lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	(3,998)
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — investor
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	530
Jan. 1, 2020	776
Provision for loan losses	(347)
Balance at end of period	431			530
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — investor | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	2
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate — investor | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	246
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	246
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	246
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Real estate construction
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	7,532
Jan. 1, 2020	25,879
Provision for loan losses	9,018
Balance at end of period	34,942			7,532
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Real estate construction | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	45
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Real estate construction | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,347
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,347
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	18,347
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate lending
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	8,062
Jan. 1, 2020	26,655
Provision for loan losses	8,671
Balance at end of period	35,373			8,062
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate lending | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	47
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Commercial real estate lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,593
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	18,593
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	18,593
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total commercial
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	20,465
Jan. 1, 2020	35,060
Provision for loan losses	15,241
Balance at end of period	50,413			20,465
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total commercial | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	112
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total commercial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	14,595
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	14,595
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	14,595
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Home equity
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	1,038
Jan. 1, 2020	3,629
Provision for loan losses	241
Balance at end of period	3,936			1,038
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Home equity | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	66
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Home equity | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,591
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,591
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	2,591
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Other consumer
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	405
Jan. 1, 2020	1,909
Provision for loan losses	17
Balance at end of period	1,926			405
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Other consumer | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	0
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Other consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	1,504
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	1,504
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	1,504
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total consumer
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	1,443
Jan. 1, 2020	5,538
Provision for loan losses	258
Balance at end of period	5,862			1,443
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total consumer | First Staunton Bancshares [Member]
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Provision for loan losses	66
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Total consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	4,095
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	4,095
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	4,095
Allowance for Loans Losses and Unfunded Commitments [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(19,308)
Recoveries	2,268
Net Charge offs	(17,040)
Allowance for PCD loans for bank acquisition	3,504
Allowance for credit losses on loans
Balance at beginning of period	223,278
Jan. 1, 2020	354,425
Charge offs	(19,308)
Recoveries	2,268
Net Charge offs	17,040
Allowance for PCD loans for bank acquisition	3,504
Provision for credit losses	50,457
Balance at end of period	394,069			223,278
Percent of Loans					1.62%
Allowance for Loans Losses and Unfunded Commitments [Member] | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	2,722
Allowance for Loans Losses and Unfunded Commitments [Member] | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	131,147
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	131,147
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	131,147
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	(15,049)
Allowance for PCD loans for bank acquisition	293
Allowance for credit losses on loans
Balance at beginning of period	103,409
Jan. 1, 2020	152,330
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	15,049
Allowance for PCD loans for bank acquisition	293
Provision for credit losses	50,745
Balance at end of period	188,788			103,409
Percent of Loans					2.22%
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and industrial | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	469
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and industrial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	48,921
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	48,921
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	48,921
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	890
Allowance for credit losses on loans
Balance at beginning of period	10,411
Jan. 1, 2020	8,560
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	890
Provision for credit losses	843
Balance at end of period	10,553			10,411
Percent of Loans					1.12%
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — owner occupied | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	259
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — owner occupied | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	(1,851)
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and business lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	(15,048)
Allowance for PCD loans for bank acquisition	1,183
Allowance for credit losses on loans
Balance at beginning of period	113,820
Jan. 1, 2020	160,890
Charge offs	(16,336)
Recoveries	1,288
Net Charge offs	15,048
Allowance for PCD loans for bank acquisition	1,183
Provision for credit losses	51,588
Balance at end of period	199,342			113,820
Percent of Loans					2.11%
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and business lending | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	728
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial and business lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	47,070
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	47,070
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	47,070
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — investor
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	753
Allowance for credit losses on loans
Balance at beginning of period	41,044
Jan. 1, 2020	43,331
Charge offs	0
Recoveries	0
Net Charge offs	0
Allowance for PCD loans for bank acquisition	753
Provision for credit losses	(2,011)
Balance at end of period	42,546			41,044
Percent of Loans					1.05%
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — investor | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	474
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate — investor | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,287
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	2,287
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	2,287
Allowance for Loans Losses and Unfunded Commitments [Member] | Real estate construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(7)
Recoveries	19
Net Charge offs	(11)
Allowance for PCD loans for bank acquisition	435
Allowance for credit losses on loans
Balance at beginning of period	32,447
Jan. 1, 2020	58,261
Charge offs	(7)
Recoveries	19
Net Charge offs	11
Allowance for PCD loans for bank acquisition	435
Provision for credit losses	6,445
Balance at end of period	65,688			32,447
Percent of Loans					4.25%
Allowance for Loans Losses and Unfunded Commitments [Member] | Real estate construction | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	537
Allowance for Loans Losses and Unfunded Commitments [Member] | Real estate construction | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	25,814
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	25,814
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	25,814
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(7)
Recoveries	19
Net Charge offs	(11)
Allowance for PCD loans for bank acquisition	1,188
Allowance for credit losses on loans
Balance at beginning of period	73,490
Jan. 1, 2020	101,591
Charge offs	(7)
Recoveries	19
Net Charge offs	11
Allowance for PCD loans for bank acquisition	1,188
Provision for credit losses	4,434
Balance at end of period	108,235			73,490
Percent of Loans					1.94%
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate lending | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	1,011
Allowance for Loans Losses and Unfunded Commitments [Member] | Commercial real estate lending | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	28,101
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	28,101
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	28,101
Allowance for Loans Losses and Unfunded Commitments [Member] | Total commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(16,343)
Recoveries	1,307
Net Charge offs	(15,037)
Allowance for PCD loans for bank acquisition	2,371
Allowance for credit losses on loans
Balance at beginning of period	187,311
Jan. 1, 2020	262,482
Charge offs	(16,343)
Recoveries	1,307
Net Charge offs	15,037
Allowance for PCD loans for bank acquisition	2,371
Provision for credit losses	56,022
Balance at end of period	307,577			187,311
Percent of Loans					2.04%
Allowance for Loans Losses and Unfunded Commitments [Member] | Total commercial | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	1,739
Allowance for Loans Losses and Unfunded Commitments [Member] | Total commercial | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	75,171
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	75,171
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	75,171
Allowance for Loans Losses and Unfunded Commitments [Member] | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(1,003)
Recoveries	91
Net Charge offs	(912)
Allowance for PCD loans for bank acquisition	651
Allowance for credit losses on loans
Balance at beginning of period	16,960
Jan. 1, 2020	50,175
Charge offs	(1,003)
Recoveries	91
Net Charge offs	912
Allowance for PCD loans for bank acquisition	651
Provision for credit losses	(6,370)
Balance at end of period	43,947			16,960
Percent of Loans					0.54%
Allowance for Loans Losses and Unfunded Commitments [Member] | Residential mortgage | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	403
Allowance for Loans Losses and Unfunded Commitments [Member] | Residential mortgage | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	33,215
Allowance for Loans Losses and Unfunded Commitments [Member] | Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(526)
Recoveries	598
Net Charge offs	(71)
Allowance for PCD loans for bank acquisition	422
Allowance for credit losses on loans
Balance at beginning of period	11,964
Jan. 1, 2020	26,204
Charge offs	(526)
Recoveries	598
Net Charge offs	71
Allowance for PCD loans for bank acquisition	422
Provision for credit losses	(894)
Balance at end of period	26,244			11,964
Percent of Loans					3.11%
Allowance for Loans Losses and Unfunded Commitments [Member] | Home equity | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	440
Allowance for Loans Losses and Unfunded Commitments [Member] | Home equity | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	14,240
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	14,240
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	14,240
Allowance for Loans Losses and Unfunded Commitments [Member] | Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(1,434)
Recoveries	272
Net Charge offs	(1,162)
Allowance for PCD loans for bank acquisition	61
Allowance for credit losses on loans
Balance at beginning of period	7,044
Jan. 1, 2020	15,564
Charge offs	(1,434)
Recoveries	272
Net Charge offs	1,162
Allowance for PCD loans for bank acquisition	61
Provision for credit losses	1,698
Balance at end of period	16,302			7,044
Percent of Loans					4.70%
Allowance for Loans Losses and Unfunded Commitments [Member] | Other consumer | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	140
Allowance for Loans Losses and Unfunded Commitments [Member] | Other consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	8,520
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	8,520
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	8,520
Allowance for Loans Losses and Unfunded Commitments [Member] | Total consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge offs	(2,963)
Recoveries	961
Net Charge offs	(2,003)
Allowance for PCD loans for bank acquisition	1,134
Allowance for credit losses on loans
Balance at beginning of period	35,968
Jan. 1, 2020	91,943
Charge offs	(2,963)
Recoveries	961
Net Charge offs	2,003
Allowance for PCD loans for bank acquisition	1,134
Provision for credit losses	(5,566)
Balance at end of period	86,493			$ 35,968
Percent of Loans					0.93%
Allowance for Loans Losses and Unfunded Commitments [Member] | Total consumer | First Staunton Bancshares [Member]
Allowance for credit losses on loans
Provision for credit losses	983
Allowance for Loans Losses and Unfunded Commitments [Member] | Total consumer | Accounting Standards Update 2016-13
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	55,975
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Cumulative effect of ASU 2016-13 adoption (CECL)	55,975
Allowance for credit losses on loans
Cumulative effect of ASU 2016-13 adoption (CECL)	$ 55,975

[1] (b) At January 1, 2020, the adoption of ASU 2016-13 resulted in an increase to the allowance for loan losses of $112 million and an increase to the allowance for unfunded commitments of $19 million for a total increase to the ACLL of $131 million. A corresponding after tax decrease to common equity of $98 million was recorded along with a deferred tax asset of $33 million, included in accrued expenses and other liabilities. Prior periods were unadjusted due to the modified retrospective application of ASU 2016-13.