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No definition available.

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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.

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- Definition

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

+ References

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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

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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- Definition

Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal 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

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

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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (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 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Notes Payable (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 08, 2017
Debt Instrument [Line Items]
Liabilities, fair value	$ 1,306	$ 1,323
Total principal amount	375,000	375,000
Less unamortized discount and debt issuance costs(3)	3,565	3,665
Notes payable	371,435	371,335
Level 2 [Member]
Debt Instrument [Line Items]
Liabilities, fair value	801	1,200
Unsecured debt [Member]
Debt Instrument [Line Items]
Interest rate			4.40%
Unsecured debt [Member] \| Borrowings [Member]
Debt Instrument [Line Items]
Liabilities, fair value	375,161	385,583
Notes payable	371,435	371,335
Unsecured debt [Member] \| Borrowings [Member] \| Level 2 [Member]
Debt Instrument [Line Items]
Liabilities, fair value	$ 375,161	385,583
Unsecured debt [Member] \| Borrowings [Member] \| Level 2 [Member] \| Unsecured Notes Two [Member]
Debt Instrument [Line Items]
Interest rate	4.40%
Unsecured debt	$ 375,000	375,000
Unsecured debt [Member] \| Borrowings [Member] \| Level 2 [Member] \| Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Liabilities, fair value	$ 0	$ 0
LIBOR [Member] \| Minimum [Member] \| Unsecured debt [Member] \| Borrowings [Member] \| Level 2 [Member] \| Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1125%
LIBOR [Member] \| Maximum [Member] \| Unsecured debt [Member] \| Borrowings [Member] \| Level 2 [Member] \| Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1625%