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

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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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Percentage of principal amount of debt redeemed.

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Amount, after accumulated amortization, of debt discount.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Long-Term Debt and Capital Lease Obligations - Note Disclosure (Details)				1 Months Ended	3 Months Ended
	Oct. 10, 2017 USD ($)	Nov. 01, 2016 USD ($)	Apr. 09, 2016	Aug. 31, 2017	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Oct. 17, 2016 USD ($)	Apr. 09, 2015
Senior Secured Credit Facilities
Interest expense					$ 8,645,000	$ 7,707,000
Sampson, LLC Drop-Down
Senior Notes Due 2021
Debt proceeds used to finance acquisition		$ 139,600,000
$55.0 Million senior unsecured notes Due 2021
Long term debt and capital lease obligations
Face amount	$ 55,000,000
Proceeds from issuance of debt	$ 60,000,000
Senior Notes Due 2021
Debt instrument redemption price percentage	106.25%
Senior Secured Credit Facilities
Unamortized discount							$ 900,000
Unamortized premium							3,400,000
Other loans
Long term debt and capital lease obligations
Long-term debt					2,022,000		2,023,000
Senior Notes
Long term debt and capital lease obligations
Long-term debt					352,372,000		352,224,000
Senior Secured Credit Facilities
Senior Notes Due 2021
Repayment of debt		159,800,000
Senior Secured Credit Facilities
Letters of credit outstanding					0		4,000,000
Line of credit amount outstanding					0		0
Commitment fee payable subject to a step down			375.00%
Senior Secured Credit Facilities \| Tranche A-1 advances
Long term debt and capital lease obligations
Long-term debt					38,629,000		39,263,000
Senior Secured Credit Facilities \| Tranche A-3 advances
Long term debt and capital lease obligations
Long-term debt					$ 4,309,000		$ 4,372,000
Senior Secured Credit Facilities \| Revolving credit commitments
Senior Secured Credit Facilities
Aggregate principal amount								$ 100,000,000
Floor rate for Eurodollar term loan borrowings								1.00%
Commitment fee payable on undrawn commitments (as a percent)			0.50%
Commitment fee payable subject to a step down			0.375%
Senior Secured Credit Facilities \| Minimum
Senior Secured Credit Facilities
Total interest coverage ratio									2.25%
Senior Secured Credit Facilities \| Maximum
Senior Secured Credit Facilities
Initial Leverage Ratio									425.00
Senior Secured Credit Facilities \| Maximum \| Revolving credit commitments
Senior Secured Credit Facilities
Total Leverage ratio			200.00%
Senior Notes Due 2021
Long term debt and capital lease obligations
Face amount		$ 300,000,000
Interest rate (as a percent)		8.50%
Senior Notes Due 2021
Percentage of ownership of notes that were tendered				100
Debt issuance costs		$ 6,400,000
Senior Notes Due 2021 \| Prior to November 1, 2018 \| Senior Notes Due 2021
Senior Notes Due 2021
Debt instrument redemption price percentage		108.50%
Senior Notes Due 2021 \| During the twelve-month period beginning November 1, 2018 \| Senior Notes Due 2021
Senior Notes Due 2021
Debt instrument redemption price percentage					104.25%
Senior Notes Due 2021 \| During the twelve-month period beginning November 1, 2019 \| Senior Notes Due 2021
Senior Notes Due 2021
Debt instrument redemption price percentage					102.125%
Senior Notes Due 2021 \| Beginning November 1, 2020 and thereafter \| Senior Notes Due 2021
Senior Notes Due 2021
Debt instrument redemption price percentage					100.00%
Senior Notes Due 2021 \| Minimum \| Prior to November 1, 2018 \| Senior Notes Due 2021
Senior Notes redemption provision
Percentage of principle required to be outstanding after redemption		65.00%
Senior Notes Due 2021 \| Maximum \| Prior to November 1, 2018 \| Senior Notes Due 2021
Senior Notes Due 2021
Percentage of principle amount to be redeemed		35.00%
Senior Notes redemption provision
Number of days in redemption period after the closing of the equity offering		120 days