CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2018		66,569
Beginning balance at Dec. 31, 2018	$ 211,689	$ 7	$ 117,763	$ 93,919
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,502			11,502
Dividends declared	(5,402)			(5,402)
Dividend equivalents on unvested performance-based restricted stock awards	0		27	(27)
Dividend equivalents canceled upon forfeiture of performance-based restricted stock awards	0		(122)	122
Restricted stock vestings (in shares)		364
Shares surrendered and cancelled upon vesting of restricted stock to satisfy tax withholdings (in shares)		(153)
Shares surrendered and canceled upon vesting of restricted stock to satisfy tax withholdings	(2,609)		(2,609)
Stock-based compensation	2,272		2,272	0
Shares issuable in lieu of dividend payments on performance-based restricted stock awards (in shares)		3
Issuance of common stock under employee stock purchase plan (in shares)		128
Issuance of common stock under employee stock purchase plan	1,443		1,443	0
Ending balance (in shares) at Mar. 31, 2019		66,911
Ending balance at Mar. 31, 2019	$ 218,895	$ 7	118,774	100,114
Beginning balance (in shares) at Dec. 31, 2019	66,968	66,968
Beginning balance at Dec. 31, 2019	$ 245,928	$ 7	123,208	122,713
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,863			11,863
Dividends declared	(6,105)			(6,105)
Dividend equivalents on unvested performance-based restricted stock awards	0		35	(35)
Dividend equivalents canceled upon forfeiture of performance-based restricted stock awards	0		(84)	84
Restricted stock vestings (in shares)		228
Shares surrendered and cancelled upon vesting of restricted stock to satisfy tax withholdings (in shares)		(91)
Shares surrendered and canceled upon vesting of restricted stock to satisfy tax withholdings	(1,865)		(1,865)
Repurchase of shares (in shares)		(241)
Repurchase of shares	(3,944)		(439)	(3,505)
Stock-based compensation	1,319		1,319	0
Issuance of common stock under employee stock purchase plan (in shares)		104
Issuance of common stock under employee stock purchase plan	$ 1,509		1,509
Ending balance (in shares) at Mar. 31, 2020	66,968	66,968
Ending balance at Mar. 31, 2020	$ 249,044	$ 7	$ 123,683	$ 125,354