Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income	$ 42,492	$ 24,971	$ 119,541	$ 58,817
Weighted Average Common Shares, Basic EPS	45,579,000	45,410,000	45,526,000	45,378,000
Weighted Average Common Shares, Dilutive effect of nonvested share awards	561,000	235,000	445,000	142,000
Weighted Average Common Shares, Diluted EPS	46,140,000	45,645,000	45,971,000	45,520,000
EPS, Basic (in dollars per share)	$ 0.93	$ 0.55	$ 2.63	$ 1.30
EPS, Dilutive effect of nonvested share awards (in dollars per share)	(0.01)	0	(0.03)	(0.01)
EPS, Diluted (in dollars per share)	$ 0.92	$ 0.55	$ 2.60	$ 1.29
Antidilutive options outstanding	0	0	0	0