Debt Securities Held-to-maturity - Credit quality indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt securities held to maturity credit quality indicator
Held to maturity securities	$ 1,953,710	$ 79,461
Obligations of Puerto Rico, States and political subdivisions
Debt securities held to maturity credit quality indicator
Held to maturity securities	66,179	73,476
Obligations of Puerto Rico, States and political subdivisions | Munis Payable From Real and Personal Property Taxes
Debt securities held to maturity credit quality indicator
Held to maturity securities	24,660	30,145
Watch | Obligations of Puerto Rico, States and political subdivisions | Munis Payable From Real and Personal Property Taxes
Debt securities held to maturity credit quality indicator
Held to maturity securities	13,735	16,345
Pass | Obligations of Puerto Rico, States and political subdivisions | Munis Payable From Real and Personal Property Taxes
Debt securities held to maturity credit quality indicator
Held to maturity securities	$ 10,925	$ 13,800