Fair Value Measurements - Non-recurring Basis (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Securities available for sale:
Non financial assets measured at fair value on a recurring basis	$ 0
Non financial liabilities measured at fair value on a recurring basis	0
Fair Value, Nonrecurring
Securities available for sale:
Fair Value, assets	24,443,000	$ 30,300,000
Fair Value, Nonrecurring | Impaired Loans
Securities available for sale:
Fair Value, assets	20,761,000	26,640,000
Fair Value, Nonrecurring | OREO
Securities available for sale:
Fair Value, assets	3,682,000	3,660,000
Fair Value, Nonrecurring | Level 2
Securities available for sale:
Fair Value, assets	3,682,000	3,660,000
Fair Value, Nonrecurring | Level 2 | OREO
Securities available for sale:
Fair Value, assets	3,682,000	3,660,000
Fair Value, Nonrecurring | Level 3
Securities available for sale:
Fair Value, assets	20,761,000	26,640,000
Fair Value, Nonrecurring | Level 3 | Impaired Loans
Securities available for sale:
Fair Value, assets	$ 20,761,000	$ 26,640,000