XML 170 R55.htm IDEA: XBRL DOCUMENT v3.21.2
Securities - Summary of Portfolio of Securities Available for Sale (Details) - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost $ 6,243,021 $ 5,743,929 [1] $ 5,841,796 [2]
Gross Unrealized Gain 101,046 130,677 [1] 77,498 [2]
Gross Unrealized Loss 150,361 29,697 [1] 33,407 [2]
Fair Value 6,193,706 5,844,909 [1] 5,885,887 [2]
Asset-backed Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost [3]   530,226 384,108
Gross Unrealized Gain [3]   2,576  
Gross Unrealized Loss [3]   5,703 10,854
Fair Value [3]   527,099 373,254
Mutual Funds      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 15,814 15,814  
Gross Unrealized Gain 116 269  
Gross Unrealized Loss 129    
Fair Value 15,801 16,083  
Mutual Funds and Common Stock      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost [4]     16,871
Gross Unrealized Gain [4]     718
Gross Unrealized Loss [4]     173
Fair Value [4]     17,416
Mortgage-Related Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 3,191,601 2,942,332 3,313,757
Gross Unrealized Gain 69,310 99,001 47,282
Gross Unrealized Loss 65,323 3,008 7,304
Fair Value 3,195,588 3,038,325 3,353,735
Mortgage-Related Securities | GSE Certificates      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 1,183,746 1,155,436 1,530,317
Gross Unrealized Gain 40,473 54,310 26,069
Gross Unrealized Loss 14,901 136 3,763
Fair Value 1,209,318 1,209,610 1,552,623
Mortgage-Related Securities | GSE CMOs      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 2,007,855 1,786,896 1,783,440
Gross Unrealized Gain 28,837 44,691 21,213
Gross Unrealized Loss 50,422 2,872 3,541
Fair Value 1,986,270 1,828,715 1,801,112
Debt Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 3,035,606 2,770,491 2,495,876
Gross Unrealized Gain 31,620 31,206 29,376
Gross Unrealized Loss 84,909 26,689 25,930
Fair Value 2,982,317 2,775,008 2,499,322
Debt Securities | U. S. Treasury Obligations      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 64,993 64,984 41,820
Gross Unrealized Gain 5 1 19
Gross Unrealized Loss     0
Fair Value 64,998 64,985 41,839
Debt Securities | GSE Debentures      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 1,433,280 1,158,253 1,093,845
Gross Unrealized Gain 2,693 3,998 5,707
Gross Unrealized Loss 67,632 3,949 5,312
Fair Value 1,368,341 1,158,302 1,094,240
Debt Securities | Asset-backed Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 520,111 530,226  
Gross Unrealized Gain 4,030 2,576  
Gross Unrealized Loss 3,368 5,703  
Fair Value 520,773 527,099  
Debt Securities | Municipal Bonds      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 25,715 25,776 26,808
Gross Unrealized Gain 482 625 559
Gross Unrealized Loss 186 90 475
Fair Value 26,011 26,311 26,892
Debt Securities | Corporate Bonds      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 870,886 870,745 854,195
Gross Unrealized Gain 16,594 17,928 15,970
Gross Unrealized Loss 5,410 6,447 2,983
Fair Value 882,070 882,226 867,182
Debt Securities | Foreign Notes      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 25,000 25,000  
Gross Unrealized Gain 993 538  
Fair Value 25,993 25,538  
Debt Securities | Capital Trust Notes      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 95,621 95,507 95,100
Gross Unrealized Gain 6,823 5,540 7,121
Gross Unrealized Loss 8,313 10,500 6,306
Fair Value 94,131 90,547 95,915
Mortgage Backed Securities And Other Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 6,227,207 5,712,823 5,809,633
Gross Unrealized Gain 100,930 130,207 76,658
Gross Unrealized Loss 150,232 29,697 33,234
Fair Value 6,177,905 5,813,333 5,853,057
Equity Securities      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost 15,814 31,106 32,163
Gross Unrealized Gain 116 470 840
Gross Unrealized Loss 129   173
Fair Value $ 15,801 31,576 32,830
Equity Securities | Preferred Stock      
Schedule of Available-for-sale Securities [Line Items]      
Amortized Cost   15,292 15,292
Gross Unrealized Gain   201 122
Gross Unrealized Loss     0
Fair Value   $ 15,493 $ 15,414
[1] Excludes accrued interest receivable of $14.9 million included in other assets in the Consolidated Statements of Condition.
[2] Excludes accrued interest receivable of $24.4 million included in other assets in the Consolidated Statements of Condition.
[3] The underlying assets of the asset-backed securities are substantially guaranteed by the U.S. Government.
[4] Primarily consists of mutual funds that are CRA-qualified investments.