Consolidated Statement Of Shareholder's Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In-Capital [Member]	Retained Earnings [Member]	Equity Attributable To Non-Controlling Interest [Member]	Total
Beginning balance at Dec. 31, 2017	$ 747	$ 274,366	$ 115,520	$ 43,021	$ 433,654
Beginning balance, shares at Dec. 31, 2017	74,734,455
Net income			20,975	2,607	23,582
Dividends to shareholders			(11,210)		(11,210)
Ending balance at Mar. 31, 2018	$ 747	274,366	125,285	45,628	446,026
Ending balance, shares at Mar. 31, 2018	74,734,455
Beginning balance at Dec. 31, 2018	$ 744	270,369	158,641	45,611	$ 475,365
Beginning balance, shares at Dec. 31, 2018					74,445,923
Net income			15,153	1,716	$ 16,869
Dividends to shareholders			(12,655)		(12,655)
Ending balance at Mar. 31, 2019	$ 744	$ 270,369	$ 161,139	$ 47,327	$ 479,579
Ending balance, shares at Mar. 31, 2019	74,445,923