Debt - March 2023 Notes (Details) - Senior Notes - March 2023 Notes	Mar. 18, 2015 USD ($)
Debt Instrument [Line Items]
Face amount of debt	$ 350,000,000.0
Interest rate (as a percent)	6.25%
From March 15, 2018 until March 15, 2021
Debt Instrument [Line Items]
Debt call price percentage	103.125%
On or After March 15, 2021
Debt Instrument [Line Items]
Debt call price percentage	100.00%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
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