v3.8.0.1

Securities - Schedule of Securities in a Continuous Unrealized Loss Position Aggregated by Investment Category and Length of Time (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Schedule Of Available For Sale Securities [Line Items] |  |
Less than 12 months, Fair Value | $ 159,181 | $ 464,524
Less than 12 months, Unrealized Loss | (1,396) | (9,784)
12 months or more, Fair Value | 268,247 |
12 months or more, Unrealized Loss | (7,898) |
Total, Fair Value | 427,428 | 464,524
Total, Unrealized Loss | (9,294) | (9,784)
U.S. Treasury Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less than 12 months, Fair Value | 197 | 297
Less than 12 months, Unrealized Loss | (2) | (3)
12 months or more, Fair Value | 296 |
12 months or more, Unrealized Loss | (4) |
Total, Fair Value | 493 | 297
Total, Unrealized Loss | (6) | (3)
Agency Mortgage-backed Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less than 12 months, Fair Value | 158,984 | 445,591
Less than 12 months, Unrealized Loss | (1,394) | (7,414)
12 months or more, Fair Value | 259,213 |
12 months or more, Unrealized Loss | (6,005) |
Total, Fair Value | 418,197 | 445,591
Total, Unrealized Loss | (7,399) | (7,414)
Beneficial interest - FHLMC securitization |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less than 12 months, Fair Value |  | 18,636
Less than 12 months, Unrealized Loss |  | (2,367)
12 months or more, Fair Value | 8,738 |
12 months or more, Unrealized Loss | (1,889) |
Total, Fair Value | 8,738 | 18,636
Total, Unrealized Loss | $ (1,889) | $ (2,367)

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
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