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Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | $ 11,293,891 | $ 11,122,696
Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 9,541 | 17,123
Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 16,461 | 5,598
Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 5,172 | 1,725
Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 77,075 | 56,410
Non-accrual loans with no ACL | 24,989 | 29,532
Non-accrual loans with ACL | 20,912 | 2,432
Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 11,216,816 | 11,066,286
Residential real estate |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 781,538 | 802,508
Residential real estate | Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 0 | 6,058
Residential real estate | Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 1,137 | 584
Residential real estate | Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 52 | 934
Residential real estate | Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 3,654 | 10,979
Non-accrual loans with no ACL | 2,173 | 3,129
Non-accrual loans with ACL | 292 | 274
Residential real estate | Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 777,884 | 791,529
Commercial real estate |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 6,912,569 | 6,315,895
Commercial real estate | Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,662 | 3,854
Commercial real estate | Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 13,538 | 2,299
Commercial real estate | Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,785 | 231
Commercial real estate | Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 29,603 | 22,201
Non-accrual loans with no ACL | 10,144 | 14,030
Non-accrual loans with ACL | 474 | 1,787
Commercial real estate | Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 6,882,966 | 6,293,694
Other commercial |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,598,616 | 3,054,817
Other commercial | Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,071 | 4,039
Other commercial | Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 862 | 809
Other commercial | Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,083 | 293
Other commercial | Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 34,810 | 14,650
Non-accrual loans with no ACL | 9,753 | 9,231
Non-accrual loans with ACL | 20,041 | 278
Other commercial | Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,563,806 | 3,040,167
Home equity |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 660,920 | 636,405
Home equity | Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,438 | 2,130
Home equity | Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 656 | 756
Home equity | Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 98 | 135
Home equity | Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 5,649 | 5,734
Non-accrual loans with no ACL | 2,406 | 2,664
Non-accrual loans with ACL | 51 | 49
Home equity | Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 655,271 | 630,671
Other consumer |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 340,248 | 313,071
Other consumer | Accruing loans 30-59 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 2,370 | 1,042
Other consumer | Accruing loans 60-89 days past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 268 | 1,150
Other consumer | Accruing loans 90 days or more past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 154 | 132
Other consumer | Past due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | 3,359 | 2,846
Non-accrual loans with no ACL | 513 | 478
Non-accrual loans with ACL | 54 | 44
Other consumer | Current loans receivable |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Loans receivable | $ 336,889 | $ 310,225

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