Parent Company Financial Information, Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Balance Sheets [Abstract]
Investment Securities	$ 548,962	$ 536,056
Total Assets	3,434,243	3,075,452
Subordinated Debentures	10,310	10,310
Liabilities	3,123,028	2,775,792
Shareholders' Equity	311,215	299,660	$ 279,981	$ 251,835
Total Liabilities and Shareholders' Equity	3,434,243	3,075,452
Parent Company [Member]
Condensed Balance Sheets [Abstract]
Cash	335	332	$ 228	$ 308
Investment in Farmers & Merchants Bank of Central California	321,134	297,643
Investment Securities	409	409
Other Assets	(57)	12,006
Total Assets	321,821	310,390
Subordinated Debentures	10,310	10,310
Liabilities	296	420
Shareholders' Equity	311,215	299,660
Total Liabilities and Shareholders' Equity	$ 321,821	$ 310,390

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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