Acquired Loans - Acquired Loans by Loan Type and Credit Quality Indicator (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		$ 91,904	$ 105,701
Acquired Loans, Aging [Abstract]
Current		89,496	104,377
Acquired Loans, Past Due		3,705	2,555
Nonaccrual	[1]	0	0
Total Acquired Loans		93,201	106,932
Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	2,951	1,546
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		5,633	5,786
Acquired Loans, Past Due		95	92
Nonaccrual	[1]	0	0
Total Acquired Loans		5,728	5,878
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	85	87
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		20,400	21,303
Acquired Loans, Past Due		1,041	1,253
Nonaccrual	[1]	0	0
Total Acquired Loans		21,441	22,556
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	510	481
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		45,531	46,795
Acquired Loans, Past Due		961	1,184
Nonaccrual	[1]	0	0
Total Acquired Loans		46,492	47,979
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	861	978
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		7,913	8,237
Acquired Loans, Past Due		113	16
Nonaccrual	[1]	0	0
Total Acquired Loans		8,026	8,253
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	113	0
Commercial and Industrial Loans [Member]
Acquired Loans, Aging [Abstract]
Current		6,359	15,267
Acquired Loans, Past Due		0	0
Nonaccrual	[1]	0	0
Total Acquired Loans		6,359	15,267
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	0	0
Consumer Loans [Member]
Acquired Loans, Aging [Abstract]
Current		934	1,346
Acquired Loans, Past Due		99	10
Nonaccrual	[1]	0	0
Total Acquired Loans		1,033	1,356
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	0	0
Other Loans [Member]
Acquired Loans, Aging [Abstract]
Current		2,726	5,643
Acquired Loans, Past Due		1,396	0
Nonaccrual	[1]	0	0
Total Acquired Loans		4,122	5,643
Other Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	1,382	0
Commercial LHFI [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		75,237	87,740
Commercial LHFI [Member] | Special Mention [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		70	71
Commercial LHFI [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		14,293	22,174
Commercial LHFI [Member] | Doubtful [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		2,814	3,058
Commercial LHFI [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		58,060	62,437
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		5,062	5,227
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Special Mention [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		26	26
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		259	278
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		4,777	4,923
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		5,176	5,371
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Special Mention [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		44	45
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		566	534
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		448	451
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		4,118	4,341
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		46,492	47,979
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		11,724	12,614
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		423	432
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		34,345	34,933
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		8,026	8,253
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		187	190
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		206	410
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		7,633	7,653
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		6,359	15,267
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		165	6,942
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Doubtful [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		1,737	1,765
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		4,457	6,560
Commercial LHFI [Member] | Other Loans [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		4,122	5,643
Commercial LHFI [Member] | Other Loans [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		1,392	1,616
Commercial LHFI [Member] | Other Loans [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		2,730	4,027
Consumer LHFI [Member]
Acquired Loans, Aging [Abstract]
Current		16,858	18,121
Subtotal		17,964	19,192
Total Acquired Loans		93,201	106,932
Consumer LHFI [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		607	586
Consumer LHFI [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		499	485
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		666	642
Subtotal		666	651
Total Acquired Loans		5,728	5,878
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due			5
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due			4
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		15,258	16,133
Subtotal		16,265	17,185
Total Acquired Loans		21,441	22,556
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		508	571
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		499	481
Consumer LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Total Acquired Loans		46,492	47,979
Consumer LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Total Acquired Loans		8,026	8,253
Consumer LHFI [Member] | Commercial and Industrial Loans [Member]
Acquired Loans, Aging [Abstract]
Total Acquired Loans		6,359	15,267
Consumer LHFI [Member] | Consumer Loans [Member]
Acquired Loans, Aging [Abstract]
Current		934	1,346
Subtotal		1,033	1,356
Total Acquired Loans		1,033	1,356
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		99	10
Consumer LHFI [Member] | Other Loans [Member]
Acquired Loans, Aging [Abstract]
Total Acquired Loans		$ 4,122	$ 5,643

[1] Acquired loans not accounted for under FASB ASC Topic 310-30.

[2] Past due 90 days or more but still accruing interest.