v3.8.0.1

Securities - Schedule of Securities in a Continuous Unrealized Loss Position Aggregated by Investment Category and Length of Time (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	$ 193,567
Less than 12 months, Unrealized Loss	(4,544)
12 months or more, Fair Value	254,029
12 months or more, Unrealized Loss	(12,119)
Total, Fair Value	447,596
Total, Unrealized Loss	(16,663)
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	197
Less than 12 months, Unrealized Loss	(2)
12 months or more, Fair Value	296
12 months or more, Unrealized Loss	(4)
Total, Fair Value	493
Total, Unrealized Loss	(6)
Agency Mortgage-backed Securities
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	193,370
Less than 12 months, Unrealized Loss	(4,542)
12 months or more, Fair Value	245,498
12 months or more, Unrealized Loss	(10,186)
Total, Fair Value	438,868
Total, Unrealized Loss	(14,728)
Beneficial interest - FHLMC securitization
Schedule Of Available For Sale Securities [Line Items]
12 months or more, Fair Value	8,235
12 months or more, Unrealized Loss	(1,929)
Total, Fair Value	8,235
Total, Unrealized Loss	$ (1,929)

X

- 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

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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
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-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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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

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+ 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
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-Topic 320
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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