Condensed Consolidated Statements of Changes in Shareholders' Equity [Unaudited] - USD ($)	Preferred Stock [Member]	Common Stock [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balances, beginning at Dec. 31, 2013	$ 0	$ 162,999,000	$ (4,101,000)	$ (5,573,000)	$ 153,325,000
Balances, ending at Jun. 30, 2014	0	318,452,000	673,000	(2,987,000)	316,138,000
Stock option exercises		75,000			75,000
Stock grants to directors for retainer fees		155,000			155,000
Stock-based compensation expense		351,000			351,000
Cash dividends		(20,102,000)	(315,000)		(20,417,000)
Common stock issued in connection with Firstbank merger (8,087,272 shares)		173,310,000			173,310,000
Stock options issued to replace existing Firstbank options at merger date		1,664,000			1,664,000
Net income			5,089,000		5,089,000
Change in net unrealized gain on securities available for sale, net of tax effect				2,667,000	2,667,000
Change in fair value of interest rate swap, net of tax effect				(81,000)	(81,000)
Balances, beginning at Dec. 31, 2014	0	317,904,000	10,218,000	16,000	328,138,000
Balances, ending at Jun. 30, 2015	$ 0	310,136,000	18,766,000	69,000	328,971,000
Employee stock purchase plan (1,110 shares)		23,000			23,000
Dividend reinvestment plan (13,788 shares)		283,000			283,000
Stock option exercises		275,000			275,000
Stock grants to directors for retainer fees		402,000			402,000
Stock-based compensation expense		359,000			359,000
Share repurchase program (463,060 shares)		$ (9,110,000)			(9,110,000)
Cash dividends			(4,656,000)		(4,656,000)
Net income			$ 13,204,000		13,204,000
Change in net unrealized gain on securities available for sale, net of tax effect				135,000	135,000
Change in fair value of interest rate swap, net of tax effect				$ (82,000)	$ (82,000)