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

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=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

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

+ 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(a)(1))
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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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ 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=6451184&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Interest and debt related expenses associated with nonoperating financing activities of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
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Balance Type:	debit
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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Balance Type:	debit
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- Definition

Fair value portion of notes payable.

+ References

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-Publisher FASB
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-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
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SENIOR UNSECURED DEBT (Narrative) (Details) - Senior Notes [Member] - USD ($)	3 Months Ended
	Mar. 31, 2017	Feb. 22, 2017	Oct. 18, 2016
Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 53,600,000.0
Stated interest rate			6.875%
Discount and direct issuance costs			$ 3,800,000
Notes payable, fair value disclosure	$ 53,000,000
Interest expense, including amortization of discount and debt issuance costs	$ 1,000,000
Senior Notes Due 2026 [Member] \| On or after August 15, 2019 [Member]
Debt Instrument [Line Items]
Redemption percentage	100.00%
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 69,000,000.0
Stated interest rate		7.25%
Discount and direct issuance costs		$ 2,600,000
Notes payable, fair value disclosure	$ 70,400,000
Interest expense	$ 800,000
Senior Notes Due 2024 [Member] \| On or after January 30, 2020 [Member]
Debt Instrument [Line Items]
Redemption percentage	100.00%