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Derivatives and Balance Sheet Offsetting (Tables) | 12 Months Ended
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Dec. 31, 2016
Derivative [Line Items] |
Balance Sheet Offsetting [Table Text Block] | The following tables show the gross interest rate swap agreements and repurchase agreements in the Consolidated Balance Sheets and the respective collateral received or pledged in the form of other financial instruments, which are generally marketable securities. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability. Therefore, instances of overcollateralization are not shown.
| Gross Amounts of Recognized Assets/Liabilities |  | Gross Amounts Offset in the Consolidated Balance Sheets |  | Net Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheets |  | Gross Amounts Not Offset in the Consolidated Balance Sheets
|  |  |  | Collateral Posted |  | Net Amount
December 31, 2016 | (in thousands)
Assets |  |  |  |  |  |  |  |  |
Interest rate contracts | $ | 9,012 |  |  | $ | — |  |  | $ | 9,012 |  |  | $ | — |  |  | $ | 9,012 |
Liabilities |  |  |  |  |  |  |  |  |
Interest rate contracts | $ | 9,036 |  |  | $ | — |  |  | $ | 9,036 |  |  | $ | (9,036 | ) |  | $ | — |
Repurchase agreements | $ | 80,822 |  |  | $ | — |  |  | $ | 80,822 |  |  | $ | (80,822 | ) |  | $ | — |
December 31, 2015 |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  |
Interest rate contracts | $ | 12,438 |  |  | $ | — |  |  | $ | 12,438 |  |  | $ | — |  |  | $ | 12,438 |
Liabilities |  |  |  |  |  |  |  |  |
Interest rate contracts | $ | 12,478 |  |  | $ | — |  |  | $ | 12,478 |  |  | $ | (12,478 | ) |  | $ | — |
Repurchase agreements | $ | 99,699 |  |  | $ | — |  |  | $ | 99,699 |  |  | $ | (99,699 | ) |  | $ | — |
Not Designated as Hedging Instrument [Member] |
Derivative [Line Items] |
Schedule of Fair Value Derivative Instruments | The following table presents the fair value and balance sheet classification of derivatives not designated as hedging instruments at December 31, 2016 and 2015:
| Asset Derivatives |  | Liability Derivatives
| 2016 |  | 2015 |  | 2016 |  | 2015
(in thousands) | Balance Sheet Location |  | Fair Value |  | Balance Sheet Location |  | Fair Value |  | Balance Sheet Location |  | Fair Value |  | Balance Sheet Location |  | Fair Value
Interest rate contracts | Other assets |  | $ | 9,012 |  |  | Other assets |  | $ | 12,438 |  |  | Other liabilities |  | $ | 9,036 |  |  | Other liabilities |  | $ | 12,478 |

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- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959 + Details
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