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Deposits - Composition of Deposits and Interest Expenses (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Time Deposits [Line Items] |  |  |
Balance | $ 7,996,524 | $ 7,420,538 | $ 7,036,576
Interest Expense | 10,757 | 35,986 | 63,026
Noninterest-bearing demand |  |  |
Time Deposits [Line Items] |  |  |
Balance | 2,748,586 | 2,261,994 | 1,698,082
Interest Expense | 0 | 0 | 0
Interest-bearing demand |  |  |
Time Deposits [Line Items] |  |  |
Balance | 979,133 | 864,510 | 962,331
Interest Expense | 809 | 2,681 | 3,915
Money market |  |  |
Time Deposits [Line Items] |  |  |
Balance | 2,070,579 | 1,937,063 | 1,949,811
Interest Expense | 3,651 | 11,645 | 30,236
Savings |  |  |
Time Deposits [Line Items] |  |  |
Balance | 1,110,155 | 969,508 | 830,919
Interest Expense | 366 | 972 | 1,928
Certificates of deposit |  |  |
Time Deposits [Line Items] |  |  |
Balance | 1,088,071 | 1,387,463 | 1,595,433
Interest Expense | $ 5,930 | $ 20,688 | $ 26,947

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- 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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- 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 + Details
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