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Loans - Investment of Originated Loans Held-for-Investment by Loan Type and Credit Quality Indicator (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | $ 2,727,852 | $ 2,678,877
Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 2,707,528 | 2,657,356
Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 3,309 | 3,349
Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 17,015 | 18,172
Real Estate | Multifamily | Less Than 35% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 197,675 | 170,832
Real Estate | Multifamily | Less Than 35% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 197,675 | 170,832
Real Estate | Multifamily | Less Than 35% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | Multifamily | Less Than 35% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | Multifamily | Equal to or Greater than 35% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,783,769 | 1,763,114
Real Estate | Multifamily | Equal to or Greater than 35% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,777,587 | 1,756,882
Real Estate | Multifamily | Equal to or Greater than 35% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 607 | 613
Real Estate | Multifamily | Equal to or Greater than 35% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 5,575 | 5,619
Real Estate | Commercial mortgage | Less Than 35% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 79,492 | 79,312
Real Estate | Commercial mortgage | Less Than 35% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 79,101 | 78,917
Real Estate | Commercial mortgage | Less Than 35% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 391 | 395
Real Estate | Commercial mortgage | Less Than 35% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | Commercial mortgage | Equal to or Greater than 35% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 423,357 | 420,548
Real Estate | Commercial mortgage | Equal to or Greater than 35% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 412,573 | 409,155
Real Estate | Commercial mortgage | Equal to or Greater than 35% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,125 | 1,137
Real Estate | Commercial mortgage | Equal to or Greater than 35% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 9,659 | 10,256
Real Estate | One-to-four family residential mortgage | Less Than 60% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 57,784 | 57,065
Real Estate | One-to-four family residential mortgage | Less Than 60% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 55,956 | 54,912
Real Estate | One-to-four family residential mortgage | Less Than 60% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 740 | 747
Real Estate | One-to-four family residential mortgage | Less Than 60% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,088 | 1,406
Real Estate | One-to-four family residential mortgage | Equal to or Greater than 60% LTV |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 34,089 | 35,368
Real Estate | One-to-four family residential mortgage | Equal to or Greater than 60% LTV | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 33,751 | 34,808
Real Estate | One-to-four family residential mortgage | Equal to or Greater than 60% LTV | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | One-to-four family residential mortgage | Equal to or Greater than 60% LTV | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 338 | 560
Real Estate | Construction and land |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 30,199 | 26,613
Real Estate | Construction and land | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 30,199 | 26,613
Real Estate | Construction and land | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | Construction and land | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Real Estate | Home equity and lines of credit |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 81,136 | 80,315
Real Estate | Home equity and lines of credit | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 80,902 | 80,077
Real Estate | Home equity and lines of credit | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 26 | 27
Real Estate | Home equity and lines of credit | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 208 | 211
Commercial and Industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 39,016 | 44,190
Commercial and Industrial | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 38,449 | 43,640
Commercial and Industrial | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 420 | 430
Commercial and Industrial | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 147 | 120
Other |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,335 | 1,520
Other | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 1,335 | 1,520
Other | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | 0 | 0
Other | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans receivable | $ 0 | $ 0

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