Net Income 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
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	57,091	6,462	15,045	5,908
Net Income	$ 18,908	$ 22,833	$ 35,742	$ 53,831
Weighted average number of common shares outstanding (for basic calculation)	20,880,000	20,622,000	20,831,000	20,577,000
Dilutive securities	626,000	898,000	714,000	969,000
Diluted (in shares)	21,506,000	21,520,000	21,545,000	21,546,000
EPS - basic	$ 0.91	$ 1.11	$ 1.72	$ 2.62
Diluted (In dollars per share)	$ 0.88	$ 1.06	$ 1.66	$ 2.50