Per Share Data (Computations of Basic Earnings Per Share and Diluted Earnings Per Share) (Details) $ / shares in Units, $ in Thousands			3 Months Ended		6 Months Ended
		Apr. 21, 2017	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares
Basic Earnings per Share:
NET INCOME | $			$ 9,839	$ 9,788	$ 19,395	$ 14,934
Weighted Average Shares Outstanding (in shares)	[1]		22,929,426	22,884,028	22,919,094	21,885,655
Basic Earnings per Share (USD per share) | $ / shares	[2]		$ 0.43	$ 0.43	$ 0.85	$ 0.68
Diluted Earnings per Share:
NET INCOME | $			$ 9,839	$ 9,788	$ 19,395	$ 14,934
Weighted Average Shares Outstanding (in shares)	[1]		22,929,426	22,884,028	22,919,094	21,885,655
Potentially Dilutive Shares, Net (in shares)			0	1,801	0	3,958
Diluted Weighted Average Shares Outstanding (in shares)	[1]		22,929,426	22,885,829	22,919,094	21,889,613
Diluted Earnings per Share (USD per share) | $ / shares	[2]		$ 0.43	$ 0.43	$ 0.85	$ 0.68
Anti-dilutive securities excluded from computation of earnings per share (in shares)			0	0	0	0
Stock split, conversion ratio		0.6667

[1] Share and per share data has been adjusted to reflect a 3-for-2 stock split on April 21, 2017.

[2] Per share data has been adjusted to reflect a 3-for-2 stock split on April 21, 2017.