| **Deposits**                      | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| **Banking and Thrift [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Deposits                          | DEPOSITSThe composition of the deposit portfolio is included in the table below for the years indicated:December 31, 2016 December 31, 2015Demand deposits$2,866,853$2,576,283Savings deposits1,560,7521,518,722Certificates and other time deposits of $100,000 or more276,274323,698Other certificates and time deposits471,247556,476Brokered deposits381,372314,468Total deposits$5,556,498$5,289,647At December 31, 2016 and 2015, deposits exceeding the FDIC's Standard Maximum Deposit Insurance Amount of $250,000 were $2.2 billion and $2.1 billion, respectively.At December 31, 2016, the contractual maturities of time deposits are summarized as follows:Certificates and Other Time Deposits2017$621,2052018230,5602019137,090202065,396202143,010After 202131,632 $1,128,893 |

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| - References
No definition available.
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| - Definition
The entire disclosure for deposit liabilities including data and tables. It may include a description of the entity's deposit liabilities, the aggregate amount of time deposits (including certificates of deposit) in denominations of $100,000 or more at the balance sheet date; the aggregate amount of any demand deposits that have been reclassified as loan balances, such as overdrafts, at the balance sheet date; deposits that are received on terms other than those in the normal course of business, the amount of accrued interest on deposit liabilities; securities, mortgage loans or other financial instruments that serve as collateral for deposits; for time deposits having a remaining term of more than one year, the aggregate amount of maturities for each of the five years following the balance sheet date; and the weighted average interest rate for all deposit liabilities held by the entity.
+ 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=d3e64164-112818Reference 2: 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
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