Shareholders' Equity (Regulatory Captial Requirements) (Details) $ in Thousands		Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Corporation [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital		$ 586,872	$ 578,137
Total Capital to Risk-Weighted Assets		0.1415	0.1401
Total Capital for Capital Adequacy Purposes		$ 331,834	$ 330,105
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets		0.0800	0.0800
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital		$ 552,481	$ 546,362
Tier 1 Capital to Risk Weighted-Assets		0.1332	0.1324
Tier 1 Capital Required For Capital Adequacy Purposes		$ 248,875	$ 247,578
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted-Assets		0.0600	0.0600
Common Equity Tier 1 Capital [Abstract]
Common Equity Tier 1 Capital		$ 530,482	$ 524,363
Common Equity Tier 1 Capital to Risk-Weighted Assets		0.1279	0.1271
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 186,656	$ 185,684
Common Equity Tier 1 Capital for Capital Adequacy Purposes to Risk-Weighted Assets		0.0450	0.0450
Tier 1 Capital (to Average Assets):
Tier 1 Leverage Capital	[1]	$ 552,481	$ 546,362
Tier 1 Leverage Capital to Average Assets	[1]	0.0946	0.0936
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	[1]	$ 233,500	$ 233,534
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	[1]	0.0400	0.0400
Bank [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital		$ 574,138	$ 565,087
Total Capital to Risk-Weighted Assets		0.1385	0.1370
Total Capital for Capital Adequacy Purposes		$ 331,722	$ 330,025
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets		0.0800	0.0800
Total Capital To Be Well Capitalized		$ 414,652	$ 412,532
Total Capital To Be Well Capitalized to Risk Weighted-Assets		0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital		$ 539,747	$ 533,312
Tier 1 Capital to Risk Weighted-Assets		0.1302	0.1293
Tier 1 Capital Required For Capital Adequacy Purposes		$ 248,791	$ 247,519
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted-Assets		0.0600	0.0600
Tier 1 Capital Required To Be Well Capitalized		$ 331,722	$ 330,025
Tier 1 Capital Required To Be Well Capitalized to Risk Weighted-Assets		0.0800	0.0800
Common Equity Tier 1 Capital [Abstract]
Common Equity Tier 1 Capital		$ 539,747	$ 533,312
Common Equity Tier 1 Capital to Risk-Weighted Assets		0.1302	0.1293
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 186,593	$ 185,639
Common Equity Tier 1 Capital for Capital Adequacy Purposes to Risk-Weighted Assets		0.0450	0.0450
Common Equity Tier 1 Capital To Be Well Capitalized		$ 269,524	$ 268,146
Common Equity Tier 1 Capital To Be Well Capitalized to Risk-Weighted Assets		0.0650	0.0650
Tier 1 Capital (to Average Assets):
Tier 1 Leverage Capital	[1]	$ 539,747	$ 533,312
Tier 1 Leverage Capital to Average Assets	[1]	0.0925	0.0914
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	[1]	$ 233,387	$ 233,434
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	[1]	0.0400	0.0400
Tier 1 Leverage Capital Required To Be Well Capitalized	[1]	$ 291,734	$ 291,793
Tier 1 Leverage Capital Required To Be Well Capitalized to Average Assets	[1]	0.0500	0.0500

[1] Leverage ratio.