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Deposits - Composition of Deposits and Interest Expenses (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | $ 7,036,576 | $ 5,673,922 | $ 5,427,891
Interest Expense | 63,026 | 40,856 | 25,330
Noninterest-bearing demand |  |  |
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | 1,698,082 | 1,421,156 | 1,387,712
Interest Expense | 0 | 0 | 0
Interest-bearing demand |  |  |
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | 962,331 | 573,693 | 603,141
Interest Expense | 3,915 | 93 | 67
Money market |  |  |
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | 1,949,811 | 1,482,065 | 1,146,156
Interest Expense | 30,236 | 20,018 | 9,204
Savings |  |  |
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | 830,919 | 784,970 | 893,119
Interest Expense | 1,928 | 1,773 | 2,081
Certificates of deposit |  |  |
Schedule Of Deposits And Borrowings Maturities [Line Items] |  |  |
Balance | 1,595,433 | 1,412,038 | 1,397,763
Interest Expense | $ 26,947 | $ 18,972 | $ 13,978

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- Definition Schedule Of Deposits And Borrowings Maturities [Line Items] + 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=6876686&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=116637391&loc=SL114874048-224260 + Details
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