Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other assets [Member]
Gross derivative positions	$ 7,006	$ 7,812
Offsetting derivative positions	5,238	5,642
Net amounts presented in balance sheet	1,768	2,170
Cash collateral pledged	0	0
Net amount	1,768	2,170
Other assets [Member] | Interest rate caps [Member]
Gross derivative positions	25	134
Offsetting derivative positions	0	0
Net amounts presented in balance sheet	25	134
Cash collateral pledged	0	0
Net amount	25	134
Other assets [Member] | Interest rate floors [Member]
Gross derivative positions	110
Offsetting derivative positions	0
Net amounts presented in balance sheet	110
Cash collateral pledged	0
Net amount	110
Other assets [Member] | Interest rate swaps [Member]
Gross derivative positions	213
Offsetting derivative positions	0
Net amounts presented in balance sheet	213
Cash collateral pledged	0
Net amount	213
Other assets [Member] | Interest rate swaps with customers [Member]
Gross derivative positions	2,857	4,920
Offsetting derivative positions	2,589	2,884
Net amounts presented in balance sheet	268	2,036
Cash collateral pledged	0	0
Net amount	268	2,036
Other assets [Member] | Mirror swaps with counterparties [Member]
Gross derivative positions	3,801	2,758
Offsetting derivative positions	2,649	2,758
Net amounts presented in balance sheet	1,152	0
Cash collateral pledged	0	0
Net amount	1,152	0
Other liabilities [Member]
Gross derivative positions	6,841	8,248
Offsetting derivative positions	5,238	5,642
Net amounts presented in balance sheet	1,603	2,606
Cash collateral pledged	1,039	1,428
Net amount	564	1,178
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	3,884	2,884
Offsetting derivative positions	2,589	2,884
Net amounts presented in balance sheet	1,295	0
Cash collateral pledged	1,025	0
Net amount	270	0
Other liabilities [Member] | Mirror swaps with counterparties [Member]
Gross derivative positions	2,917	4,986
Offsetting derivative positions	2,649	2,758
Net amounts presented in balance sheet	268	2,228
Cash collateral pledged	0	1,295
Net amount	268	$ 933
Other liabilities [Member] | Foreign exchange contract [Member]
Gross derivative positions	26
Offsetting derivative positions	0
Net amounts presented in balance sheet	26
Cash collateral pledged	0
Net amount	$ 26