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Unrealized Losses (Details 4) $ in Thousands | Dec. 31, 2018 USD ($) holding | Dec. 31, 2017 USD ($) holding
--- | --- | ---
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 205 | 163
Fair value, less than 12 months | $ 202,901 | $ 475,739
Fair value, 12 months or longer | 566,107 | 193,298
Fair value, Total | 769,008 | 669,037
Unrealized losses, Total | (19,412) | (10,384)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (2,486) | (3,465)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (16,926) | $ (6,919)
US Government Agencies Debt Securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 3 | 4
Fair value, less than 12 months | $ 9,960 | $ 24,343
Fair value, 12 months or longer | 22,078 | 0
Fair value, Total | 32,038 | 24,343
Unrealized losses, Total | (439) | (131)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (43) | (131)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (396) | $ 0
Agency mortgage-backed securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 144 | 84
Fair value, less than 12 months | $ 104,616 | $ 235,411
Fair value, 12 months or longer | 222,850 | 14,886
Fair value, Total | 327,466 | 250,297
Unrealized losses, Total | (6,510) | (1,803)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (1,363) | (1,493)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (5,147) | $ (310)
Agency collateralized mortgage obligations [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 48 | 42
Fair value, less than 12 months | $ 57,871 | $ 178,142
Fair value, 12 months or longer | 279,229 | 159,506
Fair value, Total | 337,100 | 337,648
Unrealized losses, Total | (10,355) | (7,151)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (398) | (1,579)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (9,957) | $ (5,572)
Single issuer trust preferred securities issued by banks and insurers |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 2 |
Fair value, less than 12 months | $ 2,197 |
Fair value, 12 months or longer | 0 |
Fair value, Total | 2,197 |
Unrealized losses, Total | (20) |
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (20) |
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ 0 |
Pooled trust preferred securities issued by banks and insurers |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 1 | 1
Fair value, less than 12 months | $ 0 | $ 0
Fair value, 12 months or longer | 1,329 | 1,640
Fair value, Total | 1,329 | 1,640
Unrealized losses, Total | (349) | (539)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | 0 | 0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (349) | $ (539)
Small Business Administration Pooled Securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 7 | 4
Fair value, less than 12 months | $ 28,257 | $ 34,553
Fair value, 12 months or longer | 40,621 | 9,647
Fair value, Total | 68,878 | 44,200
Unrealized losses, Total | (1,739) | (318)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (662) | (223)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | $ (1,077) | $ (95)
Marketable securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding |  | 28
Fair value, less than 12 months |  | $ 3,290
Fair value, 12 months or longer |  | 7,619
Fair value, Total |  | 10,909
Unrealized losses, Total |  | (442)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months |  | (39)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months |  | $ (403)

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