Federal Home Loan Bank Advances - Summary of Contractual Maturities of FHLB Advances (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Federal Home Loan Banks [Abstract]
Due in 2021	$ 0
Due in 2022	29,000
Due in 2023	155
Due in 2024	25,000
Due in 2025	550,000
Thereafter	1,300,000
Fair value hedge basis adjustments and unamortized prepayment fees	(14,101)	$ (7,725)
Federal Home Loan Bank advances	$ 1,890,054	$ 1,991,435

Advances From Federal Home Loan Banks, Fair Value Hedge Basis adjustments And Unamortized Prepayment Fees

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- Definition

Federal Home Loan Bank, Advance, Maturity, after Year Four

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 470
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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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