Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Article 12
-Section 13
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The premium (cost) of a hedge, net of any cash received on settlement during the period.

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- Definition

Fixed interest rate related to the interest rate derivative.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Financial Instruments - Cash Flow Hedges (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) derivative	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) derivative	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) derivative
Cash Flow Hedges
Effect of cash flow hedging relationships
Pretax gains recognized in other comprehensive income on derivatives (effective portion)	$ 178	$ 675	$ 1,341	$ 1,531
Pretax gain reclassified from accumulated other comprehensive income	0	0	0	0
Interest rate swaps
Cash flow hedges
Recognized expenses related to the ineffective portion	0	0	0	0
Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Net interest expense on derivative	$ 200	$ 600	$ 1,100	$ 1,900
Minimum \| Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Fixed interest rate (as a percent)	2.98%		2.98%		2.98%
Maximum \| Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Fixed interest rate (as a percent)	3.03%		3.03%		3.03%
Derivatives designated as hedging instruments \| Interest rate swaps
Cash flow hedges
Notional amounts	$ 192,880		$ 192,880		$ 194,687
Derivatives designated as hedging instruments \| Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Number of derivatives carried \| derivative	2		2		2
Notional amounts	$ 150,000		$ 150,000		$ 150,000
Fair value losses	$ 100		$ 100		$ 1,500