Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Founders Financial Corporation [Member]	AnchorBank WI [Member]	Common Stock [Member]	Common Stock [Member] Founders Financial Corporation [Member]	Capital Surplus [Member]	Capital Surplus [Member] Founders Financial Corporation [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Other Comprehensive Income (Loss) [Member] AnchorBank WI [Member]
Beginning Balance at Dec. 31, 2014	$ 1,465,764			$ 116,847		$ 1,118,292		$ 262,180	$ (31,555)
Net income	116,716							116,716
Other comprehensive income (loss)	(3,242)								(3,242)
Acquisition		$ 50,626			$ 3,402		$ 47,224
Dividends - common stock	(55,552)							(55,552)
Common stock issued	391			29		362
Common stock repurchased	(88,695)			(6,399)		(82,296)
Stock based compensation expense	4,255					4,255
Stock activity under incentive compensation plans	907			418		74		415
Ending Balance at Dec. 31, 2015	1,491,170			114,297		1,087,911		323,759	(34,797)
Net income	134,264							134,264
Other comprehensive income (loss)	(24,575)		$ (24,575)							$ (24,575)
Acquisition	273,565		$ 273,565	20,415		253,150
Dividends - common stock	(67,536)							(67,536)
Common stock issued	388			32		356
Common stock repurchased	(2,044)			(154)		(1,890)
Stock based compensation expense	7,318					7,318
Stock activity under incentive compensation plans	1,867			569		1,493		(195)
Ending Balance at Dec. 31, 2016	1,814,417			135,159		1,348,338		390,292	(59,372)
Net income	95,725							95,725
Other comprehensive income (loss)	9,100								9,100
Acquisition	300,828			16,527		284,301
Dividends - common stock	(72,604)							(72,604)
Common stock issued	404			24		380
Common stock repurchased	(2,761)			(153)		(2,608)
Stock based compensation expense	6,275					6,275
Stock activity under incentive compensation plans	3,013			483		2,813		(283)
Ending Balance at Dec. 31, 2017	$ 2,154,397			$ 152,040		$ 1,639,499		$ 413,130	$ (50,272)