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

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Floor rate on an interest rate derivative such as an interest rate floor or collar. If market rates falls below the floor rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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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 cash outflow for cost incurred directly with the issuance of a derivative security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Derivative Instruments (Details) - USD ($)	6 Months Ended
Derivative Instruments (Details) - USD ($)	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Derivative [Line Items]
Indebtedness, gross	$ 915,006,000		$ 766,964,000
Interest Rate Cap
Derivative [Line Items]
Notional amount	847,500,000
Indebtedness, gross	$ 906,900,000
Interest Rate Cap \| Minimum
Derivative [Line Items]
Strike rate	2.00%
Interest Rate Cap \| Maximum
Derivative [Line Items]
Strike rate	5.43%
Interest Rate Cap \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 619,500,000	$ 80,000,000
Strike rate		5.78%
Cost of derivative	$ 338,000	$ 5,000
Interest Rate Cap \| Not Designated as Hedging Instrument \| Minimum
Derivative [Line Items]
Strike rate	3.00%
Interest Rate Cap \| Not Designated as Hedging Instrument \| Maximum
Derivative [Line Items]
Strike rate	5.35%
Interest Rate Floor
Derivative [Line Items]
Notional amount	$ 3,000,000,000
Strike rate	(0.25%)
Eurodollar Future
Derivative [Line Items]
Cost of derivative	$ 0	$ 124,000