Other Real Estate Owned (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Real Estate Properties [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 25,100		$ 26,900
Total
Beginning balance	51,097	$ 61,231
Additions	17,013	26,926
Sales	(23,488)	(31,072)
Write-downs	(3,156)	(3,152)
Ending balance	43,601	53,988
Mortgage
Total
Beginning balance	19,800
Ending balance	14,300
HomeBancorp Inc.
Total
Additions	$ 2,135
Guaranty Bank
Total
Additions		$ 55