Goodwill and Intangible Assets Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Total Amortization Expense [Abstract]
Amortization of intangible assets	$ 1,356	$ 505
Estimated Amortization Expense [Abstract]
For period 04/01/19-12/31/19	3,783
For year ended 12/31/20	4,573
For year ended 12/31/21	3,996
For year ended 12/31/22	3,630
For year ended 12/31/23	3,318
For year ended 12/31/24	3,050
Core Deposits [Member]
Total Amortization Expense [Abstract]
Amortization of intangible assets	980	420
Customer Lists [Member]
Total Amortization Expense [Abstract]
Amortization of intangible assets	318	46
Mortgage Servicing Rights [Member]
Total Amortization Expense [Abstract]
Amortization of intangible assets	$ 58	$ 39	$ 308