v3.26.1
Investment Securities - Schedule of Contractual Maturities of Securities Available-for-Sale (Details)
$ in Thousands
Jun. 30, 2026
USD ($)
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 $ 0
Amortization cost, 2027 to 2031 393,827
Amortization cost, 2032 to 2036 239,495
Amortization cost, after 2036 4,062,929
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 386,576
Fair value, 2032 to 2036 229,387
Fair value, after 2036 3,868,058
Amortized cost, total 4,696,251
Fair value, total 4,484,021
Agency residential MBS  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 0
Amortization cost, after 2036 928,717
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 0
Fair value, after 2036 788,640
Amortized cost, total 928,717
Fair value, total 788,640
U.S. Treasury securities  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 223,509
Amortization cost, 2032 to 2036 0
Amortization cost, after 2036 0
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 223,475
Fair value, 2032 to 2036 0
Fair value, after 2036 0
Amortized cost, total 223,509
Fair value, total 223,475
Agency commercial MBS  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 40,179
Amortization cost, 2032 to 2036 0
Amortization cost, after 2036 110,880
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 40,031
Fair value, 2032 to 2036 0
Fair value, after 2036 109,541
Amortized cost, total 151,059
Fair value, total 149,572
Agency residential CMOs  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 13,028
Amortization cost, after 2036 2,612,261
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 13,207
Fair value, after 2036 2,586,005
Amortized cost, total 2,625,289
Fair value, total 2,599,212
Corporate debt securities  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 130,139
Amortization cost, 2032 to 2036 124,614
Amortization cost, after 2036 0
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 123,070
Fair value, 2032 to 2036 114,794
Fair value, after 2036 0
Amortized cost, total 254,753
Fair value, total 237,864
Private label residential CMOs  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 0
Amortization cost, after 2036 289,337
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 0
Fair value, after 2036 262,028
Amortized cost, total 289,337
Fair value, total 262,028
Collateralized loan obligations  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 93,763
Amortization cost, after 2036 106,544
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 93,775
Fair value, after 2036 106,725
Amortized cost, total 200,307
Fair value, total 200,500
Private label commercial MBS  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 4,870
Amortization cost, after 2036 3,076
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 4,573
Fair value, after 2036 2,938
Amortized cost, total 7,946
Fair value, total 7,511
Asset-backed securities  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 0
Amortization cost, after 2036 12,114
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 0
Fair value, after 2036 12,181
Amortized cost, total 12,114
Fair value, total 12,181
SBA securities  
Schedule of Investments [Line Items]  
Amortization cost, remainder of fiscal year 2026 0
Amortization cost, 2027 to 2031 0
Amortization cost, 2032 to 2036 3,220
Amortization cost, after 2036 0
Fair value, remainder of fiscal year 2026 0
Fair value, 2027 to 2031 0
Fair value, 2032 to 2036 3,038
Fair value, after 2036 0
Amortized cost, total 3,220
Fair value, total $ 3,038