Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite Lived Intangible Assets [Line Items]
Core deposit intangible asset	$ 587
Intangible asset amortized over estimated useful life		6 years 6 months	10 years	5 years
Customer Base Trust Intangible
Finite Lived Intangible Assets [Line Items]
Core deposit intangible asset	1,600
Manufactured Housing Servicing Intangible
Finite Lived Intangible Assets [Line Items]
Core deposit intangible asset	1,088
Clayton Banks | Core Deposits
Finite Lived Intangible Assets [Line Items]
Core deposit intangible asset	$ 9,060
Estimated useful life of intangible assets	3 years