Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	COMMON STOCK [Member]	CAPITAL SURPLUS [Member]	RETAINED EARNINGS [Member]	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) [Member]
Balance at beginning of period at Dec. 31, 2021		$ 32,603	$ 159,914	$ 977,067	$ 2,150
Shares issued for stock options		178	4,463
Net income	$ 80,622			80,622	(48,638)
Dividends on common stock				(23,582)
Stock-based compensation arrangements			918
Balance at end of period at Jun. 30, 2022	1,185,695	32,781	165,295	1,034,107	(46,488)
Balance at beginning of period at Mar. 31, 2022		32,726	163,392	1,001,200	(29,516)
Shares issued for stock options		55	1,443
Net income	44,707			44,707
Dividends on common stock				(11,800)
Stock-based compensation arrangements			460
Net change					(16,972)
Balance at end of period at Jun. 30, 2022	1,185,695	32,781	165,295	1,034,107	(46,488)
Balance at beginning of period at Dec. 31, 2022	1,250,836	32,876	169,231	1,120,292	(71,563)
Shares issued for stock options		63	1,914
Net income	112,543			112,543
Dividends on common stock				(26,336)
Stock-based compensation arrangements			1,213
Net change					558
Balance at end of period at Jun. 30, 2023	1,340,791	32,939	172,358	1,206,499	(71,005)
Balance at beginning of period at Mar. 31, 2023		32,900	170,231	1,164,665	(56,914)
Shares issued for stock options		39	1,296
Net income	55,010			55,010
Dividends on common stock				(13,176)
Stock-based compensation arrangements			831
Net change					(14,091)
Balance at end of period at Jun. 30, 2023	$ 1,340,791	$ 32,939	$ 172,358	$ 1,206,499	$ (71,005)