Fair Value Measurements - Fair values for other financial instruments that are not measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
HTM debt securities	$ 1,148,804	$ 437,193
Carrying Amount
Assets:
HTM debt securities	1,156,098	420,361
Loans, net	11,657,814	11,233,805
Liabilities:
Deposits	18,241,179	15,232,358
Long-term debt	247,360	326,956
Fair Value
Assets:
HTM debt securities	1,148,804	437,193
Loans, net	11,607,821	11,209,717
Liabilities:
Deposits	18,239,934	15,232,274
Long-term debt	267,064	336,763
Fair Value \| Level 1
Assets:
HTM debt securities	0	0
Loans, net	0	0
Liabilities:
Deposits	0	0
Long-term debt	0	0
Fair Value \| Level 2
Assets:
HTM debt securities	1,148,804	437,193
Loans, net	0	0
Liabilities:
Deposits	18,239,934	15,232,274
Long-term debt	0	0
Fair Value \| Level 3
Assets:
HTM debt securities	0	0
Loans, net	11,607,821	11,209,717
Liabilities:
Deposits	0	0
Long-term debt	$ 267,064	$ 336,763

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

No definition available.

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- References

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- References

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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