Earnings Per Share (Details) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended						9 Months Ended
		May 28, 2021	Sep. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares
Reconciliation of the component parts of earnings per share [Abstract]
Net income | $			$ 16,762	$ 14,433	$ 14,083	$ 14,071	$ 11,254	$ 13,313	$ 45,278	$ 38,638
Weighted average common shares (in shares)	[1]		19,249			19,287			19,272	19,306
Stock Options (in shares)	[1]		3			1			6	2
Weighted average common shares including potential dilutive shares (in shares)	[1]		19,252			19,288			19,278	19,308
Basic EPS (in dollars per share) | $ / shares	[1],[2]		$ 0.871			$ 0.730			$ 2.349	$ 2.002
Diluted EPS (in dollars per share) | $ / shares	[1],[2]		$ 0.871			$ 0.730			$ 2.349	$ 2.001
Reverse stock split ratio		0.2
Stock Options [Member]
Antidilutive Securities [Abstract]
Number of anti-dilutive stock options excluded from diluted earnings per share (in shares)			60			90			60	90

[1] Share and per share amounts have been adjusted for all periods presented for the 1 for 5 reverse stock split which occurred on May 28, 2021.

[2] All periods presented have been adjusted for the 1 for 5 reverse stock split which occurred on May 28, 2021.