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.

+ References

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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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.

+ References

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-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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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 gains (losses) recognized in other comprehensive loss on derivatives (effective portion)	$ 1,545	$ (819)	$ 917	$ (550)	$ 1,684	$ (1,404)
Pretax gain reclassified from accumulated other comprehensive income				(457)	387
Interest rate swaps
Cash flow hedges
Recognized expenses related to the ineffective portion	0	0	0	0	100	0
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