Represents the period from the maturity date of the debt for which the debt facility can be extended.

No definition available.

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- Definition

Maximum amount of additional loans that may be issued under the accordian feature of the debt agreement subject to receipt of lender commitments and satisfaction of certain customary conditions.

+ References

No definition available.

+ Details

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- Definition

The increase in the maximum borrowing capacity under the credit facility upon exercise of the accordion feature which is subject to receipt of lender commitments and satisfaction of certain customary conditions.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: 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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
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- Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (d)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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Bank Note Payable and Term Note Payable (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 27, 2012	Oct. 29, 2014	Aug. 26, 2013
Bank note payable and term note payable
Amount drawn down	$ 220,000,000	$ 400,000,000
Borrowings outstanding	306,500,000us-gaap_LineOfCredit		268,000,000us-gaap_LineOfCredit
BAML Revolver
Bank note payable and term note payable
Total available			500,000,000
Additional borrowing capacity allowed by exercising an accordion feature			250,000,000
Borrowings outstanding	306,500,000		268,000,000
Extension available on debt			12 months
Facility fee (as a percent)			0.25%
Weighted average interest rate (as a percent)	1.82%		1.41%
Interest rate during period (as a percent)			1.60%
BAML Revolver \| Baa1 \| BBB+
Bank note payable and term note payable
Facility fee (as a percent)			0.15%
BAML Revolver \| Baa2 \| BBB
Bank note payable and term note payable
Facility fee (as a percent)			0.20%
BAML Revolver \| Baa3 \| BBB-
Bank note payable and term note payable
Facility fee (as a percent)			0.25%
BAML Revolver \| Minimum \| A3 \| A-
Bank note payable and term note payable
Facility fee (as a percent)			0.125%
BAML Revolver \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Facility fee (as a percent)			0.30%
BAML Term Loan
Bank note payable and term note payable
Principal amount of loan			400,000,000
Amount drawn down				400,000,000
Weighted average interest rate (as a percent)			2.20%
LIBOR \| BAML Revolver
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.25%
LIBOR \| BAML Revolver \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.925%
LIBOR \| BAML Revolver \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.05%
LIBOR \| BAML Revolver \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.25%
LIBOR \| BAML Revolver \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.875%
LIBOR \| BAML Revolver \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.65%
LIBOR \| BAML Term Loan
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.45%
Fixed rate (as a percent)			0.75%
Term pursuant to interest rate swap agreement				5 years
LIBOR \| BAML Term Loan \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.025%
LIBOR \| BAML Term Loan \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.20%
LIBOR \| BAML Term Loan \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.45%
LIBOR \| BAML Term Loan \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.95%
LIBOR \| BAML Term Loan \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.90%
Base Rate \| BAML Revolver
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.25%
Base Rate \| BAML Revolver \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.00%
Base Rate \| BAML Revolver \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.05%
Base Rate \| BAML Revolver \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.25%
Base Rate \| BAML Revolver \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.00%
Base Rate \| BAML Revolver \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.65%
Base Rate \| BAML Term Loan
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.45%
Base Rate \| BAML Term Loan \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.025%
Base Rate \| BAML Term Loan \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.20%
Base Rate \| BAML Term Loan \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.45%
Base Rate \| BAML Term Loan \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.00%
Base Rate \| BAML Term Loan \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.90%
Federal Funds Rate \| BAML Credit Facility
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.50%
One month LIBOR \| BAML Credit Facility
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.00%
BMO Term Loan
Bank note payable and term note payable
Principal amount of loan						220,000,000
Amount drawn down						220,000,000
Term of the borrowing					7 years
Additional loans allowed by exercising an accordion feature					$ 50,000,000
Debt instrument overall rate (basis spread plus variable rate), end of period (as a percent)	4.22%		3.97%
BMO Term Loan \| LIBOR
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.65%
Fixed rate (as a percent)			2.32%
Term pursuant to interest rate swap agreement						7 years
BMO Term Loan \| LIBOR \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.15%
BMO Term Loan \| LIBOR \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.35%
BMO Term Loan \| LIBOR \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.65%
BMO Term Loan \| LIBOR \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.05%
BMO Term Loan \| LIBOR \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			2.15%
BMO Term Loan \| Base Rate
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.65%
BMO Term Loan \| Base Rate \| Baa1 \| BBB+
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.15%
BMO Term Loan \| Base Rate \| Baa2 \| BBB
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.35%
BMO Term Loan \| Base Rate \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.65%
BMO Term Loan \| Base Rate \| Minimum \| A3 \| A-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.05%
BMO Term Loan \| Base Rate \| Maximum \| Baa3 \| BBB-
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.15%
BMO Term Loan \| Federal Funds Rate
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			0.50%
BMO Term Loan \| One month LIBOR
Bank note payable and term note payable
Basis spread on variable rate (as a percent)			1.00%