v3.8.0.1

Securities - Summary of AFS Securities Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 526,560	$ 518,491
Gross Unrealized gains	2,098	871
Gross Unrealized losses	(9,294)	(9,784)
Estimated Fair Value	519,364	509,578
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	499	300
Gross Unrealized losses	(6)	(3)
Estimated Fair Value	493	297
Agency Mortgage-backed Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	471,131	476,163
Gross Unrealized gains	287	160
Gross Unrealized losses	(7,399)	(7,414)
Estimated Fair Value	464,019	468,909
Beneficial interest - FHLMC securitization
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	35,930	42,028
Gross Unrealized gains	1,811	711
Gross Unrealized losses	(1,889)	(2,367)
Estimated Fair Value	35,852	$ 40,372
Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	19,000
Estimated Fair Value	$ 19,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ References

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-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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