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Securities - Unrealized Loss Positions (Details) $ in Thousands	Sep. 30, 2018 USD ($) security	Dec. 31, 2017 USD ($) security
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	75	26
Greater than 12 months in an unrealized loss position | security	32	22
Total | security	107	48
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 5,117	$ 1,457
Greater than 12 months in an unrealized loss position	6,117	3,216
Total	11,234	4,673
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	247,758	102,830
Greater than 12 months in an unrealized loss position	114,923	108,651
Total	$ 362,681	$ 211,481
U.S. Treasury
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security		1
Greater than 12 months in an unrealized loss position | security	1
Total | security	1	1
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position		$ 55
Greater than 12 months in an unrealized loss position	$ 151
Total	151	55
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position		3,947
Greater than 12 months in an unrealized loss position	3,854
Total	$ 3,854	$ 3,947
U.S. government agencies
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	3	2
Greater than 12 months in an unrealized loss position | security	1
Total | security	4	2
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 109	$ 9
Greater than 12 months in an unrealized loss position	69
Total	178	9
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	7,829	6,550
Greater than 12 months in an unrealized loss position	3,874
Total	$ 11,703	$ 6,550
U.S. government agency mortgage-backed
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	6	4
Greater than 12 months in an unrealized loss position | security	7	5
Total | security	13	9
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 287	$ 24
Greater than 12 months in an unrealized loss position	421	141
Total	708	165
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	7,357	5,501
Greater than 12 months in an unrealized loss position	7,409	4,843
Total	$ 14,766	$ 10,344
States and political subdivisions
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	55	13
Greater than 12 months in an unrealized loss position | security	9	1
Total | security	64	14
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 3,843	$ 1,237
Greater than 12 months in an unrealized loss position	2,895	27
Total	6,738	1,264
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	174,924	45,985
Greater than 12 months in an unrealized loss position	28,218	1,512
Total	$ 203,142	$ 47,497
Corporate bonds
Securities Available-for-Sale, Number of Securities
Greater than 12 months in an unrealized loss position | security		1
Total | security		1
Securities Available-for-Sale, Unrealized Losses
Greater than 12 months in an unrealized loss position		$ 11
Total		11
Securities Available-for-Sale, Fair Value
Greater than 12 months in an unrealized loss position		332
Total		$ 332
Collateralized mortgage obligations
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	4	3
Greater than 12 months in an unrealized loss position | security	8	8
Total | security	12	11
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 714	$ 31
Greater than 12 months in an unrealized loss position	2,206	1,124
Total	2,920	1,155
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	25,620	11,534
Greater than 12 months in an unrealized loss position	33,342	40,219
Total	$ 58,962	$ 51,753
Asset-backed securities
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	3
Greater than 12 months in an unrealized loss position | security	5	7
Total | security	8	7
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 79
Greater than 12 months in an unrealized loss position	361	$ 1,913
Total	440	1,913
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	7,526
Greater than 12 months in an unrealized loss position	30,240	61,745
Total	$ 37,766	$ 61,745
Collateralized loan obligations
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	4	3
Greater than 12 months in an unrealized loss position | security	1
Total | security	5	3
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 85	$ 101
Greater than 12 months in an unrealized loss position	14
Total	99	101
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	24,502	29,313
Greater than 12 months in an unrealized loss position	7,986
Total	$ 32,488	$ 29,313

X

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