SHAREHOLDERS' EQUITY (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 24, 2020	Feb. 20, 2019	Feb. 21, 2018
Weighted average shares outstanding:
Weighted average basic common shares (in shares)	13,007,000	12,834,000	12,504,000
Effect of stock options (in shares)	0	747,000	1,043,000
Effect of dilutive share awards (in shares)	0	167,000	153,000
Effect of Convertible Senior Notes and warrants (in shares)	0	871,000	397,000
Weighted average diluted common shares (in shares)	13,007,000	14,619,000	14,097,000
Additional disclosure
Anti-dilutive securities excluded from calculation of diluted earnings per share	1,100,000
Common Stock Repurchases
Value of common stock authorized to be repurchased					$ 150,000,000.0	$ 100,000,000.0
Purchase of treasury stock (in shares)		22,731	379,449
Value of treasury stock acquired		$ 5,470,000	$ 92,606,000
Remaining authorized repurchase amount	$ 179,700,000
2025 Convertible Notes
Additional disclosure
Interest rate	0.50%			0.50%
Stock Options
Additional disclosure
Anti-dilutive securities excluded from calculation of diluted earnings per share	200,000	100,000	400,000