Derivatives and Hedging Activities - Offsetting Derivatives (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross Amounts of Recognized Assets	$ 7,473	$ 8,730
Gross Amounts of Recognized (Liabilities)	(10,638)	(3,886)
Gross Amounts Offset on the Balance Sheet	0	0
Net Amounts of (Liabilities) Assets presented on the Balance Sheet	(3,165)	4,844
Gross Amounts Not Offset on the Balance Sheet, Financial Instruments	(141)
Gross Amounts Not Offset on the Balance Sheet, Financial Instruments		141
Gross Amounts Not Offset on the Balance Sheet, Cash Collateral Received (Posted)	0	0
Net Amount	$ (3,306)	$ 4,985

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of obligation to return securities collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a 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. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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