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Derivative Instruments and Hedging Activities - Schedule of Gross Amounts of Derivative Assets and Derivative Liabilities (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Other Assets |  |  |
Derivatives (included in Other Assets) |  |  |
Gross amounts recognized |  | $ 5,818 | $ 4,974
Gross amounts offset |  | (1,149) | (1,900)
Net Amounts Presented in the Consolidated Balance Sheets |  | 4,669 | 3,074
Gross amounts not offset | [1] | (2,011) | 0
Net Amount |  | 2,658 | 3,074
Other Liabilities |  |  |
Derivatives (included in Other Liabilities) |  |  |
Gross amounts recognized |  | 5,914 | 4,955
Gross amounts offset |  | (1,149) | (1,900)
Net Amounts Presented in the Consolidated Balance Sheets |  | 4,765 | 3,055
Gross amounts not offset | [1] | 0 | (1,448)
Net Amount |  | $ 4,765 | $ 1,607
[1] | Amounts represent received/posted collateral.

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- Definition Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226016-175313 + Details
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