Shareholders' Equity (Summary of the Company's Common and Preferred Stock) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Common Stock:
Shares authorized (in shares)	100,000,000	100,000,000
Shares issued (in shares)	56,518,119	56,068,220
Preferred Stock:
Shares authorized (in shares)	20,000,000	20,000,000
Common stock
Common Stock:
Shares authorized (in shares)	100,000,000	100,000,000
Shares issued (in shares)	56,518,119	56,068,220
Shares outstanding (in shares)	56,407,558	55,965,207
Cash dividend per share (in usd per share)	$ 0.76	$ 0.56
Preferred stock
Preferred Stock:
Shares authorized (in shares)	20,000,000	20,000,000
Shares issued (in shares)	5,000,000	5,000,000
Shares outstanding (in shares)	5,000,000	5,000,000