Summary of Significant Accounting Policies (Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accounting Policies [Abstract]
Net income	$ 14,311	$ 24,393	$ 29,242	$ 55,283
Basic earnings per share:
Income available to common stockholders, basic	$ 14,311	$ 24,393	$ 29,242	$ 55,283
Weighted average common shares outstanding, basic (in shares)	64,315,547	64,886,149	64,350,790	64,826,714
Income available to common stockholders, per share amount, basic (usd per share)	$ 0.22	$ 0.38	$ 0.45	$ 0.85
Dilutive shares (in shares)	85,001	130,575	78,064	138,348
Diluted earnings per share:
Income available to common stockholders, diluted	$ 14,311	$ 24,393	$ 29,242	$ 55,283
Weighted average common shares outstanding, diluted (in shares)	64,400,548	65,016,724	64,428,854	64,965,062
Income available to common stockholders, per share amount, diluted (usd per share)	$ 0.22	$ 0.38	$ 0.45	$ 0.85