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Loans Receivable and Allowance for Credit Losses (Summary of Activities in Allowance for Loan Losses by Portfolio Segments and Unfunded Credit Commitments) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Financing Receivable Allowance for Credit Losses |  |  |  |
Accounting Standards Update [Extensible List] |  |  | us-gaap:AccountingStandardsUpdate201613Member |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | $ 358,287 |
Provision for (reversal of) credit losses | $ 10,000 | $ 38,284 | 186,313 | $ 80,108
Gross charge-offs | (2,800) | (36) | (2,800) | (426)
Allowance, end of period | 618,252 |  | 618,252 |
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | 10,000 | 38,284 | 186,313 | 80,108
PCD or PCI loans |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 0 |
Unfunded Credit Commitments |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Provision for (reversal of) credit losses | 111 | 405 | 7,468 | 858
Allowance for unfunded credit commitments |  |  |  |
Allowance for Unfunded Credit Commitments | 28,972 | 13,019 | 11,158 | 12,566
Provision for credit losses on unfunded credit commitments | 111 | 405 | 7,468 | 858
Allowance for Unfunded Credit Commitments | 29,083 | 13,424 | 29,083 | 13,424
Unfunded Credit Commitments | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for unfunded credit commitments |  |  |  |
Allowance for Unfunded Credit Commitments | 0 | 0 | 10,457 | 0
Commercial lending | Commercial and industrial (“C&I”) |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 380,723 | 205,503 | 238,376 | 189,117
Provision for (reversal of) credit losses | 31,691 | 37,281 | 130,171 | 78,685
Gross charge-offs | (25,111) | (25,098) | (57,466) | (54,087)
Gross recoveries | 1,218 | 1,648 | 3,395 | 5,612
Total net (charge-offs) recoveries | (23,893) | (23,450) | (54,071) | (48,475)
Foreign currency translation adjustment | 500 | (465) | 308 | (458)
Allowance, end of period | 389,021 | 218,869 | 389,021 | 218,869
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | 31,691 | 37,281 | 130,171 | 78,685
Commercial lending | Commercial and industrial (“C&I”) | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 74,237 |
Commercial lending | Commercial and industrial (“C&I”) | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 312,613 |
Commercial lending | Commercial real estate (“CRE”) |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 176,040 | 39,811 | 40,509 | 40,666
Provision for (reversal of) credit losses | (8,301) | (3,213) | 46,449 | (6,127)
Gross charge-offs | (1,414) | (1,021) | (2,688) | (1,021)
Gross recoveries | 485 | 1,896 | 10,371 | 3,955
Total net (charge-offs) recoveries | (929) | 875 | 7,683 | 2,934
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 166,810 | 37,473 | 166,810 | 37,473
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (8,301) | (3,213) | 46,449 | (6,127)
Commercial lending | Commercial real estate (“CRE”) | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 72,169 |
Commercial lending | Commercial real estate (“CRE”) | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 112,678 |
Commercial lending | Real estate loan | Multifamily residential |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 25,058 | 19,280 | 22,826 | 19,885
Provision for (reversal of) credit losses | (1,916) | 985 | 7,273 | 46
Gross charge-offs | 0 | 0 | 0 | 0
Gross recoveries | 665 | 42 | 1,820 | 376
Total net (charge-offs) recoveries | 665 | 42 | 1,820 | 376
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 23,807 | 20,307 | 23,807 | 20,307
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (1,916) | 985 | 7,273 | 46
Commercial lending | Real estate loan | Multifamily residential | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | (8,112) |
Commercial lending | Real estate loan | Multifamily residential | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 14,714 |
Commercial lending | Construction and land |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 18,551 | 22,961 | 19,404 | 20,290
Provision for (reversal of) credit losses | (8,180) | 6,189 | 828 | 8,358
Gross charge-offs | 0 | 0 | 0 | 0
Gross recoveries | 30 | 21 | 58 | 523
Total net (charge-offs) recoveries | 30 | 21 | 58 | 523
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 10,401 | 29,171 | 10,401 | 29,171
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (8,180) | 6,189 | 828 | 8,358
Commercial lending | Construction and land | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | (9,889) |
Commercial lending | Construction and land | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 9,515 |
Consumer lending | Real estate loan | Single-family residential |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 25,314 | 32,763 | 28,527 | 31,340
Provision for (reversal of) credit losses | (2,692) | (2,877) | (2,659) | (1,528)
Gross charge-offs | 0 | (11) | 0 | (11)
Gross recoveries | 0 | 60 | 424 | 134
Total net (charge-offs) recoveries | 0 | 49 | 424 | 123
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 22,622 | 29,935 | 22,622 | 29,935
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (2,692) | (2,877) | (2,659) | (1,528)
Consumer lending | Real estate loan | Single-family residential | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | (3,670) |
Consumer lending | Real estate loan | Single-family residential | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 24,857 |
Consumer lending | HELOCs |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 3,867 | 6,177 | 5,265 | 5,774
Provision for (reversal of) credit losses | (637) | (326) | (20) | 75
Gross charge-offs | 0 | 0 | (221) | 0
Gross recoveries | 43 | 5 | 47 | 7
Total net (charge-offs) recoveries | 43 | 5 | (174) | 7
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 3,273 | 5,856 | 3,273 | 5,856
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (637) | (326) | (20) | 75
Consumer lending | HELOCs | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | (1,798) |
Consumer lending | HELOCs | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 3,467 |
Consumer lending | Other consumer |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 2,518 | 4,130 | 3,380 | 4,250
Provision for (reversal of) credit losses | (76) | (160) | (3,197) | (259)
Gross charge-offs | (124) | (12) | (180) | (40)
Gross recoveries | 0 | 7 | 94 | 14
Total net (charge-offs) recoveries | (124) | (5) | (86) | (26)
Foreign currency translation adjustment |  | 0 | 0 | 0
Allowance, end of period | 2,318 | 3,965 | 2,318 | 3,965
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | (76) | (160) | (3,197) | (259)
Consumer lending | Other consumer | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 2,221 |
Consumer lending | Other consumer | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 5,601 |
Commercial and consumer lending |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period | 632,071 | 330,625 | 358,287 | 311,322
Provision for (reversal of) credit losses | 9,889 | 37,879 | 178,845 | 79,250
Gross charge-offs | (26,649) | (26,142) | (60,555) | (55,159)
Gross recoveries | 2,441 | 3,679 | 16,209 | 10,621
Total net (charge-offs) recoveries | (24,208) | (22,463) | (44,346) | (44,538)
Foreign currency translation adjustment | 500 | (465) | 308 | (458)
Allowance, end of period | 618,252 | 345,576 | 618,252 | 345,576
Allowance for unfunded credit commitments |  |  |  |
Provision for credit losses on unfunded credit commitments | $ 9,889 | $ 37,879 | 178,845 | $ 79,250
Commercial and consumer lending | Cumulative Effect, Period Of Adoption, Adjustment |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | 125,158 |
Commercial and consumer lending | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Allowance for loan losses by portfolio segments |  |  |  |
Allowance, beginning of period |  |  | $ 483,445 |

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