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Deposits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deposits, by Type [Abstract] |  |  |
Non-interest bearing demand | $ 4,633,500 | $ 3,426,500 |
Interest bearing: |  |  |
Demand | 4,118,900 | 3,195,400 |
Savings | 4,405,900 | 3,591,600 |
Total | 419,300 | 651,100 |
Time, other | 639,400 | 798,900 |
Total interest bearing | 9,583,500 | 8,237,000 |
Total deposits | 14,217,000 | 11,663,500 |
Brokered time deposits | 0 | 2,900 |
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS) | 97,300 | 117,700 |
Time deposits of $250,000 or more | 193,000 | 278,400 |
FDIC deposit insurance limit | 250,000 |  |
Time, $100 and Over |  |  |
Due within 3 months or less | 65,800 |  |
Due after 3 months and within 6 months | 77,200 |  |
Due after 6 months and within 12 months | 173,000 |  |
Due within 2022 | 81,700 |  |
Due within 2023 | 7,300 |  |
Due within 2024 | 4,000 |  |
Due within 2025 and thereafter | 10,300 |  |
Total | 419,300 | 651,100 |
Total Time |  |  |
Due within 3 months or less | 271,100 |  |
Due after 3 months and within 6 months | 190,800 |  |
Due after 6 months and within 12 months | 355,500 |  |
Due within 2022 | 171,100 |  |
Due within 2023 | 30,000 |  |
Due within 2024 | 15,200 |  |
Due within 2025 and thereafter | 25,000 |  |
Total | 1,058,700 |  |
Interest expense, time deposits, $100,000 or more | $ 6,500 | $ 11,500 | $ 5,000

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- Definition FDIC Deposit Insurance Limit + References No definition available. + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher SEC -Name Industry Guide -Number 3 -Section V -Paragraph D-E + Details
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- Definition The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice. + 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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