Components of Calculation of Basic and Diluted Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		200
Net income (loss)	$ 163,094	$ (38,697)
Weighted-average shares – basic	15,152	15,098
Effect of dilutive securities	8	0
Weighted-average shares – diluted	15,160	15,098