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Deposits - Composition of Deposits and Interest Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Time Deposits [Line Items]
Balance	$ 7,420,538	$ 7,036,576	$ 5,673,922
Interest Expense	35,986	63,026	40,856
Noninterest-bearing demand
Time Deposits [Line Items]
Balance	2,261,994	1,698,082	1,421,156
Interest Expense	0	0	0
Interest-bearing demand
Time Deposits [Line Items]
Balance	864,510	962,331	573,693
Interest Expense	2,681	3,915	93
Money market
Time Deposits [Line Items]
Balance	1,937,063	1,949,811	1,482,065
Interest Expense	11,645	30,236	20,018
Savings
Time Deposits [Line Items]
Balance	969,508	830,919	784,970
Interest Expense	972	1,928	1,773
Certificates of deposit
Time Deposits [Line Items]
Balance	1,387,463	1,595,433	1,412,038
Interest Expense	$ 20,688	$ 26,947	$ 18,972

X

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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X

- Definition

Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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- References

No definition available.

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