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)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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- Definition

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

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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- Definition

Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Derivative Financial Instruments - Cash Flow Hedges (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($) derivative	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) derivative	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) derivative	Dec. 31, 2014 USD ($) derivative
Cash Flow Hedges
Effect of cash flow hedging relationships
Pretax gain (loss) recognized in OCI on derivatives (effective portion)	$ 1,545	$ (819)	$ 917	$ (550)	$ 1,684	$ (1,404)
Pretax loss reclassified from accumulated other comprehensive income into income				457	(387)
Interest rate swaps
Cash flow hedges
Recognized expenses related to the ineffective portion	0	0	0	0	100	0
Fair value gains					1,200	300
Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Net interest expense on derivative	$ 800	$ 1,000	$ 2,500	$ 3,000	$ 3,900	$ 4,000
Minimum \| Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Fixed interest rate (as a percent)	2.98%		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%	3.03%
Derivatives designated as hedging instruments \| Interest rate swaps
Cash flow hedges
Notional amounts	$ 202,394		$ 202,394		$ 232,867	$ 284,121
Derivatives designated as hedging instruments \| Interest rate swaps \| Cash Flow Hedges
Cash flow hedges
Number of derivatives carried \| derivative	2		2		2	2
Notional amounts	$ 150,000		$ 150,000		$ 150,000	$ 150,000
Fair value losses	$ 5,600		$ 5,600		$ 6,600	$ 7,700