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Loans (Analysis of Impaired Loans) (Details) - Loans, Excluding Purchased Credit Impaired Loans [Member] $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) Modifications | Dec. 31, 2018 USD ($) Modifications | Dec. 31, 2017 USD ($) Modifications
Financing Receivable, Modifications, Number of Contracts | Modifications | 24 | 34 | 60
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 8,633,955 | $ 8,252,647 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 31,994 | 49,104 |
Recorded Investment | 483 | 3,326 |
Unpaid Principal Balance | 637 | 3,584 |
Related Allowance | 22 | 31 |
Impaired Financing Receivable, Average Recorded Investment | 42,731 | 65,461 | $ 40,650
Impaired Financing Receivable, Interest Income, Accrual Method | $ 452 | $ 1,138 | $ 971
Commercial business: Secured loans [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 11 | 12 | 10
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 3,437,564 | $ 3,286,416 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 24,083 | 26,285 |
Recorded Investment | 3,286 | 6,350 |
Unpaid Principal Balance | 3,851 | 8,460 |
Related Allowance | 93 | 2,023 |
Impaired Financing Receivable, Average Recorded Investment | 24,682 | 39,701 | $ 20,282
Impaired Financing Receivable, Interest Income, Accrual Method | $ 202 | $ 81 | $ 60
Commercial business: Unsecured loans [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 129,671 | $ 112,097 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 12 | 20 |
Recorded Investment | 12 | 20 |
Unpaid Principal Balance | 12 | 20 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 16 | 191 | $ 5
Impaired Financing Receivable, Interest Income, Accrual Method | $ 1 | $ 2 | $ 0
Real estate: One-to-four family residential [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 1 | 0 | 3
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 264,513 | $ 235,138 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 382 | 888 |
Recorded Investment | 299 | 325 |
Unpaid Principal Balance | 588 | 798 |
Related Allowance | 5 | 8 |
Impaired Financing Receivable, Average Recorded Investment | 665 | 748 | $ 730
Impaired Financing Receivable, Interest Income, Accrual Method | $ 42 | $ 42 | $ 49
Real estate: Commercial and multifamily residential: Commercial land [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 300,973 | $ 283,451 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 2,217 | 2,226 |
Recorded Investment | 1,592 | 0 |
Unpaid Principal Balance | 1,601 | 0 |
Related Allowance | 312 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 2,606 | 2,371 | $ 2,079
Impaired Financing Receivable, Interest Income, Accrual Method | $ 31 | $ 34 | $ 0
Real estate: Commercial and multifamiIy residential: Income property [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 1 | 1 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 2,059,361 | $ 1,917,522 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 2,954 |
Recorded Investment | 0 | 99 |
Unpaid Principal Balance | 0 | 165 |
Related Allowance | 0 | 1 |
Impaired Financing Receivable, Average Recorded Investment | 1,121 | 3,284 | $ 4,314
Impaired Financing Receivable, Interest Income, Accrual Method | $ 0 | $ 130 | $ 51
Real estate: Commercial and multifamiIy residential: Owner occupied [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 1,797,682 | $ 1,605,042 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 3,663 | 12,709 |
Recorded Investment | 3,663 | 3,231 |
Unpaid Principal Balance | 5,233 | 4,666 |
Related Allowance | 29 | 69 |
Impaired Financing Receivable, Average Recorded Investment | 10,681 | 9,730 | $ 5,335
Impaired Financing Receivable, Interest Income, Accrual Method | 168 | 720 | 445
Real estate construction: One-to-four family residential: Land and acquisition [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 1,364 | 4,417 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 0 | 0 | 3
Impaired Financing Receivable, Interest Income, Accrual Method | 0 | 0 | 0
Real estate construction: One-to-four family residential: Residential construction [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 190,301 | 212,396 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 0 | 484 | 309
Impaired Financing Receivable, Interest Income, Accrual Method | 0 | 0 | $ 0
Real estate construction: Commercial and multifamily residential: Income property [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 88,389 | 194,912 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | $ 0 | $ 0 |
Real estate construction: Commercial and multifamily residential: Owner occupied [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 73,203 | $ 87,063 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 0 | 3,240 | $ 1,620
Impaired Financing Receivable, Interest Income, Accrual Method | $ 0 | $ 0 | $ 203
Consumer [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 11 | 21 | 42
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 290,934 | $ 314,193 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 1,637 | 4,022 |
Impaired Financing Receivable, Average Recorded Investment | 2,960 | 5,712 | $ 5,973
Impaired Financing Receivable, Interest Income, Accrual Method | 8 | 129 | $ 163
Impaired Loans Without Recorded Allowance [Member] |  |  |
Recorded Investment | 22,659 | 35,753 |
Unpaid Principal Balance | 30,813 | 40,716 |
Impaired Loans With Recorded Allowance [Member] |  |  |
Recorded Investment | 9,335 | 13,351 |
Unpaid Principal Balance | 11,922 | 17,693 |
Related Allowance | 461 | 2,132 |
Impaired Loans Without Recorded Allowance [Member] |  |  |
Recorded Investment | 1,154 | 696 |
Unpaid Principal Balance | 1,310 | 704 |
Impaired Loans Without Recorded Allowance [Member] | Commercial business: Secured loans [Member] |  |  |
Recorded Investment | 20,797 | 19,935 |
Unpaid Principal Balance | 28,658 | 24,404 |
Impaired Loans Without Recorded Allowance [Member] | Commercial business: Unsecured loans [Member] |  |  |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: One-to-four family residential [Member] |  |  |
Recorded Investment | 83 | 563 |
Unpaid Principal Balance | 182 | 575 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamily residential: Commercial land [Member] |  |  |
Recorded Investment | 625 | 2,226 |
Unpaid Principal Balance | 663 | 2,272 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamiIy residential: Income property [Member] |  |  |
Recorded Investment | 0 | 2,855 |
Unpaid Principal Balance | 0 | 3,011 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamiIy residential: Owner occupied [Member] |  |  |
Recorded Investment | 0 | 9,478 |
Unpaid Principal Balance | 0 | 9,750 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: One-to-four family residential: Land and acquisition [Member] |  |  |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: One-to-four family residential: Residential construction [Member] |  |  |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: Commercial and multifamily residential: Income property [Member] |  |  |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: Commercial and multifamily residential: Owner occupied [Member] |  |  |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | $ 0 | $ 0 |

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