Securities - Securities in Unrealized Loss Position (Details) $ in Thousands	Mar. 31, 2019 USD ($) security	Dec. 31, 2018 USD ($) security
Available for sale at fair value:
Available for sale, Total number in a loss position \| security	40	45
Available for sale, Less than 12 months Estimated fair value	$ 1,691	$ 5,416
Available for sale, Less than 12 months, Unrealized loss	(2)	(53)
Available for sale, 12 Months and greater Estimated fair value	36,476	35,038
Available for sale, 12 Months and greater Unrealized loss	(965)	(1,197)
Available for sale, Estimated fair value	38,167	40,454
Available for sale, Unrealized loss	$ 967	$ 1,250
Held to maturity at cost:
Held to maturity, Total number in a loss position \| security	10	9
Held to maturity, Less than 12 months Estimated fair value	$ 1,512	$ 1,277
Held to maturity, Less than 12 months Unrealized loss	(1)	(15)
Held to maturity, 12 months and greater, Estimated fair value		6,687
Held to maturity, 12 months and greater, Unrealized loss		(269)
Held to maturity, Total Estimated fair value		7,964
Held to maturity, Total Unrealized loss		$ (284)
Equity Securities:
Equity securities, 12 months and greater, Estimated fair value	7,948
Equity securities, 12 months and greater, Unrealized loss	(223)
Equity securities, Total estimated fair value	9,460
Equity securities, Total unrealized loss	$ (224)
U.S. Government sponsored entities
Available for sale at fair value:
Available for sale, Total number in a loss position \| security	5	5
Available for sale, Less than 12 months Estimated fair value	$ 0	$ 0
Available for sale, Less than 12 months, Unrealized loss	0	0
Available for sale, 12 Months and greater Estimated fair value	5,678	5,642
Available for sale, 12 Months and greater Unrealized loss	(78)	(116)
Available for sale, Estimated fair value	5,678	5,642
Available for sale, Unrealized loss	$ 78	$ 116
Held to maturity at cost:
Held to maturity, Total number in a loss position \| security	2	2
Held to maturity, Less than 12 months Estimated fair value	$ 0	$ 0
Held to maturity, Less than 12 months Unrealized loss	0	0
Held to maturity, 12 months and greater, Estimated fair value	2,445	2,434
Held to maturity, 12 months and greater, Unrealized loss	(82)	(94)
Held to maturity, Total Estimated fair value	2,445	2,434
Held to maturity, Total Unrealized loss	$ (82)	$ (94)
State and political subdivisions
Available for sale at fair value:
Available for sale, Total number in a loss position \| security	2	4
Available for sale, Less than 12 months Estimated fair value	$ 0	$ 0
Available for sale, Less than 12 months, Unrealized loss	0	0
Available for sale, 12 Months and greater Estimated fair value	1,765	3,129
Available for sale, 12 Months and greater Unrealized loss	(65)	(120)
Available for sale, Estimated fair value	1,765	3,129
Available for sale, Unrealized loss	$ 65	$ 120
Residential mortgage-backed securities
Available for sale at fair value:
Available for sale, Total number in a loss position \| security	28	31
Available for sale, Less than 12 months Estimated fair value	$ 1,691	$ 4,445
Available for sale, Less than 12 months, Unrealized loss	(2)	(23)
Available for sale, 12 Months and greater Estimated fair value	22,241	20,480
Available for sale, 12 Months and greater Unrealized loss	(465)	(597)
Available for sale, Estimated fair value	23,932	24,925
Available for sale, Unrealized loss	$ 467	$ 620
Held to maturity at cost:
Held to maturity, Total number in a loss position \| security	5	5
Held to maturity, Less than 12 months Estimated fair value	$ 0	$ 1,277
Held to maturity, Less than 12 months Unrealized loss	0	(15)
Held to maturity, 12 months and greater, Estimated fair value	2,070	821
Held to maturity, 12 months and greater, Unrealized loss	(34)	(37)
Held to maturity, Total Estimated fair value	2,070	2,098
Held to maturity, Total Unrealized loss	$ (34)	$ (52)
Commercial mortgage-backed securities
Held to maturity at cost:
Held to maturity, Total number in a loss position \| security	2	2
Held to maturity, Less than 12 months Estimated fair value	$ 0	$ 0
Held to maturity, Less than 12 months Unrealized loss	0	0
Held to maturity, 12 months and greater, Estimated fair value	3,433	3,432
Held to maturity, 12 months and greater, Unrealized loss	(107)	(138)
Held to maturity, Total Estimated fair value	3,433	3,432
Held to maturity, Total Unrealized loss	$ (107)	$ (138)
Corporate and other securities
Available for sale at fair value:
Available for sale, Total number in a loss position \| security	5	5
Available for sale, Less than 12 months Estimated fair value	$ 0	$ 971
Available for sale, Less than 12 months, Unrealized loss	0	(30)
Available for sale, 12 Months and greater Estimated fair value	6,792	5,787
Available for sale, 12 Months and greater Unrealized loss	(357)	(364)
Available for sale, Estimated fair value	6,792	6,758
Available for sale, Unrealized loss	$ 357	$ 394
Held to maturity at cost:
Held to maturity, Total number in a loss position \| security	1
Held to maturity, Less than 12 months Estimated fair value	$ 1,512
Held to maturity, Less than 12 months Unrealized loss	(1)
Held to maturity, 12 months and greater, Estimated fair value	0
Held to maturity, 12 months and greater, Unrealized loss	0
Held to maturity, Total Estimated fair value	1,512
Held to maturity, Total Unrealized loss	$ (1)

Trading Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss

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Trading Securities, Continuous Unrealized Loss Position, Accumulated Loss

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

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