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Securities (Unrealized Loss NOT deemed to be OTTI) (Details) $ in Thousands | Jun. 30, 2018 USD ($) holding | Dec. 31, 2017 USD ($) holding
--- | --- | ---
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 214 | 163
Fair value, less than 12 months | $ 702,667 | $ 475,739
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (18,608) | (3,465)
Fair value, 12 months or longer | 162,613 | 193,298
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | (9,668) | (6,919)
Fair value, Total | 865,280 | 669,037
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (28,276) | $ (10,384)
U. S. Government Agency Securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 4 | 4
Fair value, less than 12 months | $ 32,719 | $ 24,343
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (760) | (131)
Fair value, 12 months or longer | 0 | 0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months |  | 0
Fair value, Total | 32,719 | 24,343
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (760) | $ (131)
Agency mortgage-backed securities |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 151 | 84
Fair value, less than 12 months | $ 341,018 | $ 235,411
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (9,349) | (1,493)
Fair value, 12 months or longer | 14,003 | 14,886
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | (675) | (310)
Fair value, Total | 355,021 | 250,297
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (10,024) | $ (1,803)
Agency Collateralized Mortgage Obligations [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 52 | 42
Fair value, less than 12 months | $ 274,293 | $ 178,142
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (7,235) | (1,579)
Fair value, 12 months or longer | 137,912 | 159,506
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | (8,385) | (5,572)
Fair value, Total | 412,205 | 337,648
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (15,620) | $ (7,151)
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
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | 0 | 0
Fair value, 12 months or longer | 1,751 | 1,640
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | (415) | (539)
Fair value, Total | 1,751 | 1,640
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (415) | $ (539)
Equity securities |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding |  | 28
Fair value, less than 12 months |  | $ 3,290
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months |  | (39)
Fair value, 12 months or longer |  | 7,619
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months |  | (403)
Fair value, Total |  | 10,909
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss |  | $ (442)
Small Business Administration Pooled Securities [Member] |  |
Summary of gross unrealized losses and fair value of investments |  |
No of holdings | holding | 6 | 4
Fair value, less than 12 months | $ 54,637 | $ 34,553
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months | (1,264) | (223)
Fair value, 12 months or longer | 8,947 | 9,647
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months | (193) | (95)
Fair value, Total | 63,584 | 44,200
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss | $ (1,457) | $ (318)

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