Financial Instruments: Derivatives and Hedging (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)
Financial Instruments: Derivatives and Hedging
Unrealized gains or losses on derivative financial instruments in accumulated other comprehensive income		$ 5,100
Interest reclassified from accumulated other comprehensive income into interest expense		4,000
Amount estimated to be reclassified into earnings within next 12 months	$ 3,200	3,200
Loss on Cash Flow Hedge Ineffectiveness		388
Hedge ineffectiveness	(600)	$ 400
BMO Term Loan \| BAML Term Loan
Financial Instruments: Derivatives and Hedging
Percentage floor of spread payable to the counterparty		0.00%
BMO Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 220,000	$ 220,000
Strike Rate (as a percent)	2.32%	2.32%
Fair Value	$ (11,589)	$ (11,589)
Fair Value	11,600	11,600
BAML Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 400,000	$ 400,000
Strike Rate (as a percent)	0.75%	0.75%
Fair Value	$ (269)	$ (269)
Fair Value	300	300
2017 Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 400,000	$ 400,000
Strike Rate (as a percent)	1.12%	1.12%
Fair Value	$ (793)	$ (793)
Fair Value	$ 800	$ 800

Represents the percentage floor of the spread payable to the counterparty should the base rate be negative.

No definition available.

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- Definition

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

+ References

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

+ Details

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ 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

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow 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 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

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- Definition

The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e689-108580

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41638-113959

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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