CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY, (Unaudited) - USD ($)	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]
Balances at Dec. 31, 2017	$ 462,211,000	$ 531,000	$ 461,680,000	$ 0
Increase (Decrease) in Stockholders' Equity
Net income	(16,377,000)	0	0	(16,377,000)
Cash dividend declared	(16,463,000)	0	(16,463,000)	0
Issuance of common shares pursuant to stock based compensation plan	35,000	0	35,000	0
Amortization of stock based compensation	45,000	0	45,000	0
Stock Repurchased and Retired During Period, Value		0	0	0
Balances at Mar. 31, 2018	429,451,000	531,000	445,297,000	(16,377,000)
Balances at Dec. 31, 2018	336,079,000	491,000	379,975,000	(44,387,000)
Increase (Decrease) in Stockholders' Equity
Net income	10,597,000	0	0	10,597,000
Cash dividend declared	11,824,000	0	11,824,000	0
Issuance of common stock pursuant to public offerings, net	8,503,000	13,000	8,490,000	0
Issuance of common shares pursuant to stock based compensation plan	41,000	0	41,000	0
Amortization of stock based compensation	42,000	0	42,000	0
Stock Repurchased and Retired During Period, Value	(3,024,000)	(5,000)	(3,019,000)	0
Balances at Mar. 31, 2019	$ 340,414,000	$ 499,000	$ 373,705,000	$ (33,790,000)