Income Taxes, Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax Provision at Federal Statutory Rate									$ 12,543	$ 19,068	$ 16,037
Interest on Obligations of States and Political Subdivisions exempt from Federal Taxation									(338)	(617)	(675)
State and Local Income Taxes, Net of Federal Income Tax Benefit									4,791	3,573	2,992
Bank Owned Life Insurance									(434)	(696)	(731)
Low-Income Housing Tax Credit									(1,624)	(1,546)	(1,201)
Out of Period Adjustment									(802)	0	0
Bargain Purchase Gain									0	0	(641)
Deferred Tax Asset Remeasurement									0	6,256	0
Other, Net									67	73	316
Total Provision for Taxes	$ 4,258	$ 2,995	$ 3,589	$ 3,361	$ 11,974	$ 5,000	$ 4,708	$ 4,429	$ 14,203	$ 26,111	$ 16,097
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Tax Provision at Federal Statutory Rate									21.00%	35.00%	35.00%
Interest on Obligations of States and Political Subdivisions exempt from Federal Taxation									(0.60%)	(1.10%)	(1.50%)
State and Local Income Taxes, Net of Federal Income Tax Benefit									7.90%	6.50%	6.50%
Bank Owned Life Insurance									(0.70%)	(1.30%)	(1.60%)
Low-Income Housing Tax Credit									(2.70%)	(2.80%)	(2.60%)
Out of Period Adjustment									(1.30%)	(0.00%)	(0.00%)
Bargain Purchase Gain									(0.00%)	(0.00%)	(1.40%)
Deferred Tax Asset Remeasurement									0.00%	11.50%	0.00%
Other, Net									0.10%	0.10%	0.70%
Total Provision for Taxes									23.80%	47.90%	35.10%