Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2016	$ 201,344	$ 1,365	$ 224,739	$ (44)	$ (24,716)
Balance, shares at Dec. 31, 2016		136,475,000
Restricted stock issued and vesting of restricted stock units, net		$ 10	(10)
Restricted stock issued and vesting of restricted stock units net, shares		1,022,000
Shares repurchased	(7,891)	$ (7)	(7,884)
Shares repurchased, shares		(698,000)
Exercise of stock options, net	532	$ 2	530
Exercise of stock options net, shares		197,000
Stock-based compensation	14,717		14,717
Tax benefit from stock option exercised and vested restricted shares	492		492
Other comprehensive income	335			335
Dividends	(43,777)		(16,578)		(27,199)
Net income (loss)	27,199				27,199
Balance at Dec. 31, 2017	192,951	$ 1,370	216,006	291	(24,716)
Balance, shares at Dec. 31, 2017		136,996,000
Common stock issued (Note 3)	137,250	$ 153	137,097
Common stock issued, shares		15,250,000
Restricted stock issued and vesting of restricted stock units, net		$ 9	(9)
Restricted stock issued and vesting of restricted stock units net, shares		759,000
Shares repurchased	(2,885)		(2,885)
Shares repurchased, shares		(334,000)
Exercise of stock options, net	191		191
Exercise of stock options net, shares		531,000
Stock-based compensation	13,255		13,255
Other comprehensive income	176			176
Dividends	(19,236)				(19,236)
Net income (loss)	36,633				36,633
Balance at Dec. 31, 2018	$ 358,335	$ 1,532	363,655	467	(7,319)
Balance, shares at Dec. 31, 2018	153,202,000	153,202,000
Restricted stock issued and vesting of restricted stock units, net		$ 22	(22)
Restricted stock issued and vesting of restricted stock units net, shares		2,347,000
Shares repurchased	$ (2,341)	$ (1)	(2,340)
Shares repurchased, shares		(370,000)
Exercise of stock options, net	160		160
Exercise of stock options net, shares		85,000
Stock-based compensation	11,590		11,590
Other comprehensive income	478			478
Dividends	(20,385)		(20,385)
Net income (loss)	(10,425)				(10,425)
Balance at Dec. 31, 2019	$ 337,412	$ 1,553	$ 352,658	$ 945	$ (17,744)
Balance, shares at Dec. 31, 2019	155,264,000	155,264,000