Goodwill and Intangible Assets Mortgage Servicing Rights (Details) - USD ($)		3 Months Ended		12 Months Ended
	May 01, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets		$ (1,356,000)	$ (505,000)
Mortgage Servicing Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		0	0	$ 1,558,000
Capitalization Of Mortgage Servicing Rights		0	0	7,000
Amortization of Intangible Assets		(58,000)	(39,000)	(308,000)
Finite-Lived Intangible Assets, Net		$ 2,043,000	$ 805,000	$ 2,101,000	$ 844,000
First BancTrust [Member] | Mortgage Servicing Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 1,558,000