CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY, (Unaudited) - USD ($)	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]
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)
Common Stock Shares Outstanding, Beginning Balance at Dec. 31, 2018	49,132,000	49,132,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues		1,268,000
Stock Issued During Period Shares Share Based Compensation	7,000	7,000
Stock Repurchased and Retired During Period, Shares		(469,000)
Common Stock Shares Outstanding, Ending Balance at Mar. 31, 2019	49,938,000	49,938,000
Balances at Dec. 31, 2018	$ 336,079,000	$ 491,000	379,975,000	(44,387,000)
Increase (Decrease) in Stockholders' Equity
Net income	5,653,000
Balances at Sep. 30, 2019	$ 391,988,000	$ 631,000	430,091,000	(38,734,000)
Common Stock Shares Outstanding, Beginning Balance at Dec. 31, 2018	49,132,000	49,132,000
Common Stock Shares Outstanding, Ending Balance at Sep. 30, 2019		63,058,000
Balances at Dec. 31, 2018	$ 336,079,000	$ 491,000	379,975,000	(44,387,000)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock pursuant to public offerings, net	92,314,000
Balances at Dec. 31, 2019	$ 395,507,000	$ 631,000	414,998,000	(20,122,000)
Common Stock Shares Outstanding, Beginning Balance at Dec. 31, 2018	49,132,000	49,132,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues	14,377,126
Common Stock Shares Outstanding, Ending Balance at Dec. 31, 2019	63,061,781	63,062,000
Balances at Mar. 31, 2019	$ 340,414,000	$ 499,000	373,705,000	(33,790,000)
Increase (Decrease) in Stockholders' Equity
Net income	3,533,000	0	0	3,533,000
Cash dividend declared	12,859,000	0	12,859,000	0
Issuance of common stock pursuant to public offerings, net	28,495,000	44,000	28,451,000	0
Issuance of common shares pursuant to stock based compensation plan	43,000	0	43,000	0
Amortization of stock based compensation	32,000	0	32,000	0
Balances at Jun. 30, 2019	$ 359,658,000	$ 543,000	389,372,000	(30,257,000)
Common Stock Shares Outstanding, Beginning Balance at Mar. 31, 2019	49,938,000	49,938,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues		4,338,000
Stock Issued During Period Shares Share Based Compensation		7,000
Stock Repurchased and Retired During Period, Shares		0
Common Stock Shares Outstanding, Ending Balance at Jun. 30, 2019		54,283,000
Increase (Decrease) in Stockholders' Equity
Net income	$ (8,477,000)	$ 0	0	(8,477,000)
Cash dividend declared	14,588,000	0	14,588,000	0
Issuance of common stock pursuant to public offerings, net	55,324,000	88,000	55,236,000	0
Issuance of common shares pursuant to stock based compensation plan	48,000	0	48,000	0
Amortization of stock based compensation	23,000	0	23,000	0
Balances at Sep. 30, 2019	391,988,000	$ 631,000	430,091,000	(38,734,000)
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues		8,771,000
Stock Issued During Period Shares Share Based Compensation		4,000
Common Stock Shares Outstanding, Ending Balance at Sep. 30, 2019		63,058,000
Balances at Dec. 31, 2019	395,507,000	$ 631,000	414,998,000	(20,122,000)
Increase (Decrease) in Stockholders' Equity
Net income	(91,199,000)	0	0	(91,199,000)
Cash dividend declared	15,670,000	0	15,670,000	0
Issuance of common stock pursuant to public offerings, net	19,447,000	31,000	19,416,000	0
Issuance of common shares pursuant to stock based compensation plan	0	0	0	0
Amortization of stock based compensation	59,000	0	59,000	0
Stock Repurchased and Retired During Period, Value	0	0	0	0
Balances at Mar. 31, 2020	$ 308,144,000	$ 662,000	418,803,000	(111,321,000)
Common Stock Shares Outstanding, Beginning Balance at Dec. 31, 2019	63,061,781	63,062,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues	3,171,000	3,171,000
Stock Issued During Period Shares Share Based Compensation	4,000	4,000
Common Stock Shares Outstanding, Ending Balance at Mar. 31, 2020		66,237,000
Balances at Dec. 31, 2019	$ 395,507,000	$ 631,000	414,998,000	(20,122,000)
Increase (Decrease) in Stockholders' Equity
Net income	(14,351,000)
Issuance of common stock pursuant to public offerings, net	35,013,000
Balances at Sep. 30, 2020	$ 376,741,000	$ 693,000	410,521,000	(34,473,000)
Common Stock Shares Outstanding, Beginning Balance at Dec. 31, 2019	63,061,781	63,062,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues	6,244,053,000
Common Stock Shares Outstanding, Ending Balance at Sep. 30, 2020	69,295,962	69,296,000
Balances at Mar. 31, 2020	$ 308,144,000	$ 662,000	418,803,000	(111,321,000)
Increase (Decrease) in Stockholders' Equity
Net income	48,772,000	0	0	48,772,000
Cash dividend declared	10,935,000	0	10,935,000	0
Issuance of common stock pursuant to public offerings, net	0	0	0	0
Issuance of common shares pursuant to stock based compensation plan	0	0	0	0
Amortization of stock based compensation	55,000	0	55,000	0
Stock Repurchased and Retired During Period, Value	(68,000)	0	(68,000)	0
Balances at Jun. 30, 2020	345,968,000	$ 662,000	407,855,000	(62,549,000)
Common Stock Shares Outstanding, Beginning Balance at Mar. 31, 2020		66,237,000
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares Share Based Compensation		4,000
Stock Repurchased and Retired During Period, Shares		(20,000)
Common Stock Shares Outstanding, Ending Balance at Jun. 30, 2020		66,221,000
Increase (Decrease) in Stockholders' Equity
Net income	28,076,000	$ 0	0	28,076,000
Cash dividend declared	12,920,000	0	12,920,000	0
Issuance of common stock pursuant to public offerings, net	15,566,000	31,000	15,535,000	0
Issuance of common shares pursuant to stock based compensation plan	(2,000)	0	(2,000)	0
Amortization of stock based compensation	53,000	0	53,000	0
Balances at Sep. 30, 2020	$ 376,741,000	$ 693,000	$ 410,521,000	$ (34,473,000)
Increase (Decrease) in Stockholders' Equity
Stock Issued During Period Shares New Issues		3,073,000
Stock Issued During Period Shares Share Based Compensation		2,000
Common Stock Shares Outstanding, Ending Balance at Sep. 30, 2020	69,295,962	69,296,000