Parent Company Financial Information, Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Statements of Income [Abstract]
Interest Income	$ 86,750	$ 78,708	$ 73,640
Tax Benefit	(16,924)	(15,094)	(14,221)
Net Income	27,392	25,402	24,061
Parent Company [Member]
Condensed Statements of Income [Abstract]
Equity in Undistributed Earnings in Farmers & Merchants Bank of Central California	17,352	18,211	14,352
Dividends from Subsidiary	10,875	8,000	10,450
Interest Income	10	10	10
Other Expenses, Net	(1,451)	(1,406)	(1,288)
Tax Benefit	606	587	537
Net Income	$ 27,392	$ 25,402	$ 24,061