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Securities - Summary of Gross Unrealized Losses and Fair Values, Aggregated by Investment Category and Length of Individual Securities Continuous Unrealized Loss Position Held-to-maturity (Details) $ in Thousands | Dec. 31, 2018 USD ($) Security
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Schedule Of Held To Maturity Securities [Line Items] |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Number of Securities | Security | 46
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | $ 36,251
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | (711)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 42,862
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | (949)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Fair Value | 79,113
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Unrealized Losses | $ (1,660)
Obligations of States, Municipalities, and Political Subdivisions |
Schedule Of Held To Maturity Securities [Line Items] |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Number of Securities | Security | 23
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | $ 8,127
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | (58)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 8,792
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | (152)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Fair Value | 16,919
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Unrealized Losses | $ (210)
Agency, Residential Mortgage-Backed Securities |
Schedule Of Held To Maturity Securities [Line Items] |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Number of Securities | Security | 16
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | $ 6,625
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | (150)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 21,139
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | (381)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Fair Value | 27,764
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Unrealized Losses | $ (531)
Non-Agency, Residential Mortgage-Backed Securities |
Schedule Of Held To Maturity Securities [Line Items] |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Number of Securities | Security | 7
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | $ 21,499
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | (503)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 12,931
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | (416)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Fair Value | 34,430
Held-to-maturity Securities, Continuous Unrealized Loss Position, Total Unrealized Losses | $ (919)

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- Definition Held to maturity securities in unrealized loss positions qualitative disclosure number of securities. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 + Details
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