Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Consolidated Statements of Comprehensive Income (Unaudited) [Abstract]
Net Income	$ 10,550	$ 8,187	$ 20,491	$ 16,008
Other Comprehensive Income
Increase in Net Unrealized (Loss) Gain on Available-for-Sale Securities	(2,519)	898	(7,807)	784
Deferred Tax Benefit (Expense) Related to Unrealized Gains	757	(378)	2,320	(330)
Reclassification Adjustment for Realized Losses (Gains) on Available-for-Sale Securities Included in Net Income	1,330	(131)	1,330	(131)
Deferred Tax Benefit (Expense) Related to Reclassification Adjustment	(405)	56	(405)	56
Change in Net Unrealized (Losses) Gains on Available-for-Sale Securities, Net of Tax	(837)	445	(4,562)	379
Total Other Comprehensive (Loss) Income	(837)	445	(4,562)	379
Comprehensive Income	$ 9,713	$ 8,632	$ 15,929	$ 16,387

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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