Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other assets [Member]
Gross derivative positions	$ 20,328	$ 7,006
Offsetting derivative positions	872	5,238
Net amounts presented in balance sheet	19,456	1,768
Cash collateral pledged	0	0
Net amount	19,456	1,768
Other assets [Member] | Interest rate floors [Member]
Gross derivative positions	14	110
Offsetting derivative positions	0	0
Net amounts presented in balance sheet	14	110
Cash collateral pledged	0	0
Net amount	14	110
Other assets [Member] | Interest rate caps [Member]
Gross derivative positions	83	25
Offsetting derivative positions	0	0
Net amounts presented in balance sheet	83	25
Cash collateral pledged	0	0
Net amount	83	25
Other assets [Member] | Interest rate swaps [Member]
Gross derivative positions	1,947	213
Offsetting derivative positions	0	0
Net amounts presented in balance sheet	1,947	213
Cash collateral pledged	0	0
Net amount	1,947	213
Other assets [Member] | Interest rate swaps with customers [Member]
Gross derivative positions	463	2,857
Offsetting derivative positions	430	2,589
Net amounts presented in balance sheet	33	268
Cash collateral pledged	0	0
Net amount	33	268
Other assets [Member] | Mirror swaps with counterparties [Member]
Gross derivative positions	17,784	3,801
Offsetting derivative positions	442	2,649
Net amounts presented in balance sheet	17,342	1,152
Cash collateral pledged	0	0
Net amount	17,342	1,152
Other assets [Member] | Foreign exchange contracts [Member]
Gross derivative positions	37
Offsetting derivative positions	0
Net amounts presented in balance sheet	37
Cash collateral pledged	0
Net amount	37
Other liabilities [Member]
Gross derivative positions	18,427	6,841
Offsetting derivative positions	872	5,238
Net amounts presented in balance sheet	17,555	1,603
Cash collateral pledged	0	1,039
Net amount	17,555	564
Other liabilities [Member] | Interest rate swaps [Member]
Gross derivative positions		14
Offsetting derivative positions		0
Net amounts presented in balance sheet		14
Cash collateral pledged		14
Net amount		0
Other liabilities [Member] | Interest rate swaps with customers [Member]
Gross derivative positions	17,952	3,884
Offsetting derivative positions	430	2,589
Net amounts presented in balance sheet	17,522	1,295
Cash collateral pledged	0	1,025
Net amount	17,522	270
Other liabilities [Member] | Mirror swaps with counterparties [Member]
Gross derivative positions	475	2,917
Offsetting derivative positions	442	2,649
Net amounts presented in balance sheet	33	268
Cash collateral pledged	0	0
Net amount	$ 33	268
Other liabilities [Member] | Foreign exchange contracts [Member]
Gross derivative positions		26
Offsetting derivative positions		0
Net amounts presented in balance sheet		26
Cash collateral pledged		0
Net amount		$ 26