Debt Securities - Additional Information (Details) $ in Thousands	Mar. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Available for Sale
Debt securities with gross unrealized losses, fair value | $	$ 2,593,774	$ 2,783,177
Gross unrealized losses on debt securities | $	$ 139,329	$ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses	5.40%	2.00%
Count of debt securities | security	1,185	1,252
Count of debt securities in an unrealized loss position | security	645	373
Held to Maturity
Debt securities with gross unrealized losses, fair value | $	$ 942,846
Gross unrealized losses on debt securities | $	$ 33,235
Ratio of gross unrealized losses to debt securities with gross unrealized losses	3.50%
Count of debt securities | security	55
Count of debt securities in an unrealized loss position | security	55
Total
Debt securities with gross unrealized losses, fair value | $	$ 3,536,620	$ 2,783,177
Gross unrealized losses on debt securities | $	$ 172,564	$ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses	4.90%	2.00%
Count of debt securities | security	1,240	1,252
Count of debt securities in an unrealized loss position | security	700	373