Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

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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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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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Organization and Summary of Significant Accounting Policies - Fair value (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value of Financial Instruments
Debt instrument, Carrying Value	$ 1,877.1	$ 1,275.0
5.75% senior subordinated notes due 2022
Fair Value of Financial Instruments
Interest rate (as a percent)	5.75%	5.75%
Debt instrument, Carrying Value	$ 545.1	$ 544.3
5.75% senior subordinated notes due 2022 \| Fair Value, Inputs, Level 2
Fair Value of Financial Instruments
Debt instrument, Carrying Value	545.1	544.3
Debt instrument, Fair Value	$ 567.6	$ 558.6
5.375% Senior Subordinated Notes Due 2024
Fair Value of Financial Instruments
Interest rate (as a percent)	5.375%	5.375%	5.375%
Debt instrument, Carrying Value	$ 296.8	$ 296.4
5.375% Senior Subordinated Notes Due 2024 \| Fair Value, Inputs, Level 2
Fair Value of Financial Instruments
Debt instrument, Carrying Value	296.8	296.4
Debt instrument, Fair Value	$ 293.0	295.7
5.50% senior subordinated notes due 2026
Fair Value of Financial Instruments
Interest rate (as a percent)	5.50%
Debt instrument, Carrying Value	$ 493.7
5.50% senior subordinated notes due 2026 \| Fair Value, Inputs, Level 2
Fair Value of Financial Instruments
Debt instrument, Carrying Value	493.7
Debt instrument, Fair Value	489.4
Mortgage facilities
Fair Value of Financial Instruments
Debt instrument, Carrying Value	199.9	165.8
Mortgage facilities \| Fair Value, Inputs, Level 2
Fair Value of Financial Instruments
Debt instrument, Carrying Value	199.9	165.8
Debt instrument, Fair Value	$ 195.6	$ 165.8