Amortization of debt issuance costs.

No definition available.

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- Definition

Debt instrument maturity year.

+ References

No definition available.

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- Definition

Maximum indebtedness under potential new credit facilities in aggregate principal amount.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

+ References

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

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

+ References

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

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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- Definition

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

+ References

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- Definition

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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

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

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

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

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- Definition

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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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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Notes Payable - Additional Information (Detail) - USD ($)			3 Months Ended			6 Months Ended
	Dec. 18, 2017	Apr. 10, 2017	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2014
Debt Instrument [Line Items]
Interest expense			$ 5,301,000	$ 4,843,000		$ 10,501,000	$ 7,269,000
Secured Credit Facilities [Member]
Debt Instrument [Line Items]
Interest expense					$ 2,426,000
8.0% Senior Secured Notes due 2024 [Member]
Debt Instrument [Line Items]
Issuance of debt		$ 250,000,000
Note bears interest rate		8.00%
Debt instrument, maturity year		2024
Debt instrument, frequency of periodic payment		semi-annually
Interest payment beginning date		Oct. 01, 2017
Maximum aggregate indebtedness outstanding		$ 50,000,000
Debt issuance costs			5,431,000			5,431,000
Amortization of debt issuance costs			194,000	$ 174,000		388,000	$ 174,000
Interest expense			5,194,000			$ 10,388,000
8.0% Senior Secured Notes due 2024 [Member] \| Any Time Before April 1, 2020 [Member] \| Redemption Price Plus "Make-Whole" Premium and Accrued and Unpaid Interest [Member]
Debt Instrument [Line Items]
Debt redemption price percentage of principal amount		100.00%
8.0% Senior Secured Notes due 2024 [Member] \| Any Time Before April 1, 2020 [Member] \| Redemption Price Plus Accrued and Unpaid Interest [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt redemption price percentage of principal amount		35.00%
Credit Agreement [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Issuance of debt								$ 45,000,000
Note bears interest rate								9.50%
Secured Credit Facilities , Maturity period						5 years
Credit Agreement [Member] \| Secured Credit Facilities [Member]
Debt Instrument [Line Items]
Termination of outstanding credit facilities		$ 150,000,000
Payment fee		1,500,000
Unamortized debt issuance cost and fees		$ 2,368,000
Credit Agreement [Member] \| Secured Credit Facilities [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Interest rate, Percentage						3.75%
Interest rate, Description						Base rate plus 3.75%
Credit Agreement [Member] \| Secured Credit Facilities [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Interest rate, Percentage						4.75%
Interest rate, Description						LIBOR plus 4.75%
Credit Agreement [Member] \| Secured Credit Facilities [Member] \| LIBOR Floor [Member]
Debt Instrument [Line Items]
Interest rate, Percentage						1.00%
Interest rate, Description						LIBOR floor of 1.00%
Credit Agreement [Member] \| Maximum [Member] \| Initial Term Loan Facility [Member]
Debt Instrument [Line Items]
Issuance of debt								$ 70,000,000
Credit Agreement [Member] \| Maximum [Member] \| Term B2 Facility [Member]
Debt Instrument [Line Items]
Issuance of debt								10,000,000
Credit Agreement [Member] \| Maximum [Member] \| Term B3 Facility [Member]
Debt Instrument [Line Items]
Issuance of debt								70,000,000
Credit Agreement [Member] \| Maximum [Member] \| Secured Credit Facilities [Member]
Debt Instrument [Line Items]
Issuance of debt								160,000,000
Credit Agreement [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Issuance of debt								$ 10,000,000
Revolving Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Dec. 18, 2022
Interest rate, Description						The Revolving Credit Facility will bear interest at an alternative base rate or an adjusted LIBOR, plus an applicable margin of 1.50% in the case of alternative base rate loans and 2.50% in the case of adjusted LIBOR loans.
Amounts outstanding under Revolving Credit Facility			$ 0			$ 0
Revolving Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Alternative Base Rate [Member]
Debt Instrument [Line Items]
Interest rate, Percentage	1.50%
Revolving Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Adjusted LIBOR [Member]
Debt Instrument [Line Items]
Interest rate, Percentage	2.50%
Revolving Credit Agreement [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Issuance of debt	$ 25,000,000