Line Of Credit Facility, Maturity Extension Period

No definition available.

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- Definition

Line Of Credit Facility, Maximum Maturity Extension Period

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Number of Maturity Extension Periods

+ References

No definition available.

+ Details

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- 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 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: 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=64930785&loc=d3e28551-108399

+ Details

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Balance Type:	credit
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

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ 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.

+ Details

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Period Type:	duration

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- 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

Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ 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
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

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

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

+ Details

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- Details

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Debt (Details)		12 Months Ended
Debt (Details)	Jan. 04, 2018 USD ($)	Dec. 31, 2017 USD ($) period	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate		3.48%	3.43%
Amount of indebtedness outstanding		$ 1,726,927,000	$ 2,020,475,000
Interest paid		$ 67,600,000	69,000,000	$ 76,400,000
Secured (Fixed)
Debt Instrument [Line Items]
Weighted average interest rate		3.81%
Amount of indebtedness outstanding		$ 191,616,000	332,744,000
Net premium, discounts, and unamortized debt issuance costs		$ 946,000	1,161,000
Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Weighted average interest rate		3.43%
Amount of indebtedness outstanding		$ 1,535,311,000	1,687,731,000
Net premium, discounts, and unamortized debt issuance costs		(7,689,000)	(10,269,000)
$140 Million WDC Fixed-Rate Loans \| Secured (Fixed)
Debt Instrument [Line Items]
Repayments of debt		$ 140,000,000
Interest rate percentage		5.76%
Effective rate percentage		5.76%
Amount of indebtedness outstanding		$ 0	140,000,000
Face amount of facility		$ 140,000,000
$35 Million Fixed-Rate Loan \| Secured (Fixed)
Debt Instrument [Line Items]
Interest rate percentage		5.55%
Effective rate percentage		3.75%
Amount of indebtedness outstanding		$ 30,670,000	31,583,000
Face amount of facility		$ 35,000,000	35,000,000
$160.0 Million Fixed Rate Loan \| Secured (Fixed)
Debt Instrument [Line Items]
Interest rate percentage		3.48%
Effective rate percentage		3.58%
Amount of indebtedness outstanding		$ 160,000,000	160,000,000
Face amount of facility		$ 160,000,000
$170 Million Unsecured 2015 Term Loan \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Effective rate percentage		2.54%
Amount of indebtedness outstanding		$ 170,000,000	170,000,000
Face amount of facility		$ 170,000,000
$170 Million Unsecured 2015 Term Loan \| Unsecured (Variable and Fixed) \| LIBOR
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.125%
$300 Million Unsecured 2013 Term Loan \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Amount of indebtedness outstanding		$ 300,000,000	300,000,000
Face amount of facility		$ 300,000,000
$300 Million Unsecured 2013 Term Loan \| Unsecured (Variable and Fixed) \| Interest rate swap liability
Debt Instrument [Line Items]
Effective rate percentage		2.78%
$300 Million Unsecured 2013 Term Loan \| Unsecured (Variable and Fixed) \| LIBOR
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.20%
$500 Million Unsecured 2015 Line of Credit \| Unsecured (Variable and Fixed) \| Line of Credit
Debt Instrument [Line Items]
Amount of line of credit		$ 500,000,000
Net borrowings incurred		$ 155,000,000
Effective rate percentage		2.57%
Amount of indebtedness outstanding		$ 23,000,000	178,000,000
Face amount of facility		$ 500,000,000
Additional extension period		1 year
Number of extension periods \| period		2
Extension period		6 months
$500 Million Unsecured 2015 Line of Credit \| Unsecured (Variable and Fixed) \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.00%
$300 Million Unsecured 2011 Term Loan \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Amount of indebtedness outstanding		$ 300,000,000	300,000,000
Face amount of facility		$ 300,000,000
$300 Million Unsecured 2011 Term Loan \| Unsecured (Variable and Fixed) \| Interest rate swap liability
Debt Instrument [Line Items]
Effective rate percentage		3.35%
$300 Million Unsecured 2011 Term Loan \| Unsecured (Variable and Fixed) \| LIBOR
Debt Instrument [Line Items]
Basis Spread on Variable Rate		1.15%
$350 Million Unsecured Senior Notes \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Interest rate percentage		3.40%
Effective rate percentage		3.43%
Amount of indebtedness outstanding		$ 350,000,000	350,000,000
Face amount of facility		$ 350,000,000
$400 Million Unsecured Senior Notes \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Interest rate percentage		4.45%
Effective rate percentage		4.10%
Amount of indebtedness outstanding		$ 400,000,000	$ 400,000,000
Face amount of facility		$ 400,000,000
Subsequent Event \| $170 Million Unsecured 2015 Term Loan \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Repayments of debt	$ 170,000,000
Subsequent Event \| $300 Million Unsecured 2013 Term Loan \| Unsecured (Variable and Fixed)
Debt Instrument [Line Items]
Repayments of debt	300,000,000
Subsequent Event \| $500 Million Unsecured 2015 Line of Credit \| Unsecured (Variable and Fixed) \| Line of Credit
Debt Instrument [Line Items]
Amount of line of credit	$ 500,000,000