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Deposits (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Deposits, by Type [Abstract] |  |  |
Non-interest bearing demand | $ 2,900,042,000 | $ 1,906,257,000 |
Interest bearing: |  |  |
Demand | 2,787,500,000 | 2,276,500,000 |
Savings | 3,095,400,000 | 2,141,800,000 |
Time, $100 and over | 432,000,000 | 461,400,000 |
Time, other | 720,000,000 | 590,100,000 |
Total interest bearing | 7,034,829,000 | 5,469,853,000 |
Total deposits | 9,934,871,000 | 7,376,110,000 |
Brokered time deposits | 0 | 0 |
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS) | 94,200,000 | 25,700,000 |
Time deposits of $250,000 or more | 182,000,000 | 208,500,000 |
FDIC deposit insurance limit | 250,000 |  |
Time, $100 and Over |  |  |
Due within 3 months or less | 88,600,000 |  |
Due after 3 months and within 6 months | 65,300,000 |  |
Due after 6 months and within 12 months | 110,600,000 |  |
Due after 12 months | 167,500,000 |  |
Total | 432,000,000 | 461,400,000 |
Total Time |  |  |
Due within 3 months or less | 313,800,000 |  |
Due after 3 months and within 6 months | 167,300,000 |  |
Due after 6 months and within 12 months | 259,200,000 |  |
Due after 12 months | 411,600,000 |  |
Total | 1,151,900,000 |  |
Interest expense, time deposits, $100,000 or more | $ 4,300,000 | $ 3,700,000 | $ 3,700,000

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- Definition FDIC Deposit Insurance Limit + References No definition available. + Details
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- Definition Time Deposits Obtained, Certificate of Deposit Account Registry Service + 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://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 3 -Section V -Paragraph D-E + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within six to twelve months after the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 3 -Section V -Paragraph D-E + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 3 -Section V -Paragraph D-E + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three to six months after the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 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://www.xbrl.org/2003/role/presentationRef -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 Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 The aggregate of all domestic and foreign interest-bearing deposit liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.6) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Amount of time deposits maturing after the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818 + Details
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