Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The components of accumulated other comprehensive income (loss) included in stockholders’ equity as of December 31, 2017 and 2016 are as follows (in thousands):

	Unrealized Gain (Loss) on Securities			Securities with Other-Than-Temporary Impairment Losses			Total
December 31, 2017
Net unrealized losses on securities available-for-sale	$	(2,619	)	$	—		$	(2,619	)
Unamortized losses on securities held-to-maturity transferred from available-for-sale	(281		)	—			(281		)
Securities with other-than-temporary impairment losses	—			(345		)	(345		)
Tax benefit	841			100			941
Balance at December 31, 2017	$	(2,059	)	$	(245	)	$	(2,304	)
December 31, 2016
Net unrealized losses on securities available-for-sale	$	(7,649	)	$	—		$	(7,649	)
Unamortized losses on securities held-to-maturity transferred from available-for-sale	(393		)	—			(393		)
Securities with other-than-temporary impairment losses	—			(1,398		)	(1,398		)
Tax benefit	3,134			545			3,679
Balance at December 31, 2016	$	(4,908	)	$	(853	)	$	(5,761	)

Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income [Table Text Block]

Amounts reclassified from accumulated other comprehensive income and the affected line items in the statements of income during the years ended December 31, 2017, 2016 and 2015 , were as follows (in thousands):

	Amounts Reclassified from Other Comprehensive Income									Affected Line Item in the Statements of Income
	2017			2016			2015
Realized gains on available-for-sale securities	$	616		1,192			452			Securities gains, net (Total reclassified amount before tax)
	(216		)	(465		)	(176		)	Tax expense
Total reclassifications out of accumulated other comprehensive income	$	400		$	727		$	276		Net reclassified amount