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Loans (Analysis of Impaired Loans) (Details) - Loans, Excluding Purchased Credit Impaired Loans [Member] $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) Modifications | Dec. 31, 2015 USD ($) Modifications | Dec. 31, 2014 USD ($) Modifications
Financing Receivable, Modifications, Number of Contracts | Modifications | 54 | 7 | 8
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 6,042,304 | $ 5,618,041 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 25,459 | 16,080 |
Recorded Investment | 4,464 | 15 |
Unpaid Principal Balance | 4,558 | 15 |
Related Allowance | 57 | 15 |
Impaired Financing Receivable, Average Recorded Investment | 21,493 | 22,372 | $ 26,635
Impaired Financing Receivable, Interest Income, Accrual Method | $ 237 | $ 202 | $ 1,327
Commercial business: Secured loans [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 9 | 5 | 4
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 2,442,772 | $ 2,257,168 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 8,818 | 5,524 |
Recorded Investment | 2,414 | 690 |
Unpaid Principal Balance | 2,484 | 718 |
Related Allowance | 664 | 321 |
Impaired Financing Receivable, Average Recorded Investment | 9,368 | 7,987 | $ 7,345
Impaired Financing Receivable, Interest Income, Accrual Method | 79 | 84 | 36
Commercial business: Unsecured loans [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 94,737 | 94,948 |
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 | 19
Impaired Financing Receivable, Interest Income, Accrual Method | $ 0 | $ 0 | $ 1
Real estate: One-to-four family residential [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 3 | 1 | 2
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 167,403 | $ 172,150 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 529 | 1,286 |
Recorded Investment | 435 | 314 |
Unpaid Principal Balance | 693 | 339 |
Related Allowance | 12 | 314 |
Impaired Financing Receivable, Average Recorded Investment | 743 | 2,848 | $ 2,094
Impaired Financing Receivable, Interest Income, Accrual Method | 10 | 47 | 49
Real estate: Commercial and multifamily residential: Commercial land [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 270,106 | 213,158 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 708 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 425 | 94 | 82
Impaired Financing Receivable, Interest Income, Accrual Method | $ 0 | $ 0 | $ 0
Real estate: Commercial and multifamiIy residential: Income property [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 1,365,321 | $ 1,308,673 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 4,425 | 2,106 |
Recorded Investment | 540 | 0 |
Unpaid Principal Balance | 544 | 0 |
Related Allowance | 27 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 2,492 | 2,913 | $ 6,782
Impaired Financing Receivable, Interest Income, Accrual Method | $ 26 | $ 36 | $ 270
Real estate: Commercial and multifamiIy residential: Owner occupied [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 1 | 0 | 1
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 1,054,564 | $ 940,261 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 5,414 | 6,055 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 5,084 | 7,052 | $ 9,472
Impaired Financing Receivable, Interest Income, Accrual Method | 0 | 26 | 956
Real estate construction: One-to-four family residential: Land and acquisition [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 11,542 | 14,283 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 14 | 467 |
Recorded Investment | 14 | 0 |
Unpaid Principal Balance | 102 | 0 |
Related Allowance | 1 | 0 |
Impaired Financing Receivable, Average Recorded Investment | 199 | 641 | 694
Impaired Financing Receivable, Interest Income, Accrual Method | 0 | 5 | 6
Real estate construction: One-to-four family residential: Residential construction [Member] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 109,293 | 119,813 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 336 | 562 |
Recorded Investment | 0 | 335 |
Unpaid Principal Balance | 0 | 335 |
Related Allowance | 0 | 3 |
Impaired Financing Receivable, Average Recorded Investment | 472 | 648 | 0
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 | 103,779 | 83,634 |
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] |  |  |
Recorded Investment of Loans Collectively Measured for Contingency Provision | 103,480 | 81,671 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 0 | 0 |
Recorded Investment | 0 | 0 |
Unpaid Principal Balance | 0 | 0 |
Related Allowance | $ 0 | $ 0 |
Consumer [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | Modifications | 41 | 1 | 0
Recorded Investment of Loans Collectively Measured for Contingency Provision | $ 319,307 | $ 332,282 |
Recorded Investment of Loans Individually Measured for Specific Impairment | 5,215 | 80 |
Impaired Financing Receivable, Average Recorded Investment | 2,710 | 189 | $ 147
Impaired Financing Receivable, Interest Income, Accrual Method | 122 | 4 | $ 9
Impaired Loans Without Recorded Allowance [Member] |  |  |
Recorded Investment | 17,592 | 14,726 |
Unpaid Principal Balance | 27,228 | 19,547 |
Impaired Loans With Recorded Allowance [Member] |  |  |
Recorded Investment | 7,867 | 1,354 |
Unpaid Principal Balance | 8,381 | 1,407 |
Related Allowance | 761 | 653 |
Impaired Loans Without Recorded Allowance [Member] |  |  |
Recorded Investment | 751 | 65 |
Unpaid Principal Balance | 833 | 139 |
Impaired Loans Without Recorded Allowance [Member] | Commercial business: Secured loans [Member] |  |  |
Recorded Investment | 6,404 | 4,834 |
Unpaid Principal Balance | 12,831 | 6,455 |
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 | 94 | 972 |
Unpaid Principal Balance | 291 | 1,397 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamily residential: Commercial land [Member] |  |  |
Recorded Investment | 708 | 0 |
Unpaid Principal Balance | 687 | 0 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamiIy residential: Income property [Member] |  |  |
Recorded Investment | 3,885 | 2,106 |
Unpaid Principal Balance | 4,148 | 2,311 |
Impaired Loans Without Recorded Allowance [Member] | Real estate: Commercial and multifamiIy residential: Owner occupied [Member] |  |  |
Recorded Investment | 5,414 | 6,055 |
Unpaid Principal Balance | 8,102 | 8,528 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: One-to-four family residential: Land and acquisition [Member] |  |  |
Recorded Investment | 0 | 467 |
Unpaid Principal Balance | 0 | 490 |
Impaired Loans Without Recorded Allowance [Member] | Real estate construction: One-to-four family residential: Residential construction [Member] |  |  |
Recorded Investment | 336 | 227 |
Unpaid Principal Balance | 336 | 227 |
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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