Consolidated Statement of Shareholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Midwest Bancshares, Inc. Common Stock	Ohio Heritage Bancorp, Inc. Common Stock	North Akron Savings Bank Common Stock
Balance at beginning of period at Dec. 31, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 20,385		$ 20,385
Other comprehensive income, net of tax	(758)			(758)
Repurchase of preferred shares and common stock warrant	(1,201)	1,201
Cash dividends declared	(4,807)		(4,807)
Tax benefit from exercise of stock options	16	16
Reissuance of treasury stock for deferred compensation plan for Boards of Directors	(163)				(163)
Purchase of treasury stock	156				156
Common shares issued under dividend reinvestment plan	357	357
Common shares issued under compensation plan for Board of Directors	(130)	44			(174)
Stock-based compensation expense	942	942
Balance at end of period at Dec. 31, 2012	221,728	167,039	69,158	654	(15,123)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	17,574		17,574
Other comprehensive income, net of tax	(13,898)			(13,898)
Repurchase of preferred shares and common stock warrant	0
Cash dividends declared	(5,834)		(5,834)
Tax benefit from exercise of stock options	79	79
Reissuance of treasury stock for deferred compensation plan for Boards of Directors	(168)				(168)
Purchase of treasury stock	228				228
Common shares issued under dividend reinvestment plan	423	423
Common shares issued under compensation plan for Board of Directors	179	(34)			213
Stock-based compensation expense	1,362	1,362
Balance at end of period at Dec. 31, 2013	221,553	168,869	80,898	(13,244)	(14,970)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,684		16,684
Other comprehensive income, net of tax	11,943			11,943
Repurchase of preferred shares and common stock warrant	0
Cash dividends declared	(7,191)		(7,191)
Stock Issued During Period, Value, Stock Options Exercised	72				72
Tax benefit from exercise of stock options	85	85
Reissuance of treasury stock for deferred compensation plan for Boards of Directors	(175)				(175)
Reissuance of treasury stock for common stock awards	0	10			(10)
Purchase of treasury stock	520				520
Common shares issued under dividend reinvestment plan	409	409
Common shares issued under compensation plan for Board of Directors	207	(14)			221
Stock-based compensation expense	2,111	1,813
Value of Treasury Stock Issued for Unrestricted Stock Grant to Employees					298
Stock Issued During Period, Value, Acquisitions						6,305	32,017	16,106
Proceeds from Issuance of Private Placement		40,162
Balance at end of period at Dec. 31, 2014	$ 340,118	$ 265,742	$ 90,391	$ (1,301)	$ (14,714)