Long-Term Obligations - 6.75% Senior Notes Due 2025 (Details) - Senior Notes - Senior 2025 Notes - USD ($)	May 23, 2017	Mar. 31, 2018
Debt Instrument [Line Items]
Face amount of debt	$ 250,000,000.0
Interest rate (as percent)	6.75%
Long-term Line of Credit		$ 250,000,000
Deferred financing costs		5,300,000
Debt discount		$ 1,700,000
Anytime prior to May 15, 2020
Debt Instrument [Line Items]
Redemption price, percentage of principal amount redeemed (as percent)	35.00%
Redemption price (as percent)	106.75%
Twelve-month period beginning on May 15, 2020
Debt Instrument [Line Items]
Redemption price (as percent)	105.063%
Twelve-month period beginning on May 15, 2021
Debt Instrument [Line Items]
Redemption price (as percent)	103.375%
Twelve-month period beginning on May 15, 2022
Debt Instrument [Line Items]
Redemption price (as percent)	101.688%
Beginning on May 15, 2023 and thereafter
Debt Instrument [Line Items]
Redemption price (as percent)	100.00%

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=64930739&loc=d3e28878-108400

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

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Percentage of principal amount of debt redeemed.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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