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Represents the excess cash flow used to prepay the debt.

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Represents the percentage of excess cash flow used to prepay the debt.

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The variable rate percentage (such as LIBOR) that serves as the reference rate for the debt instrument.

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Represents the amount of premium paid on repayment of debt.

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

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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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.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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.

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

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Amount of the required periodic payments applied to principal.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of interest capitalized during the period.

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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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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Long-Term Debt (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Long-term debt
Long-term debt		$ 293,138
Original issue discount		(7,092)	$ (8,959)
Total		286,046	287,179
Current		3,000	3,000
Long-term debt		283,046	284,179
Underwriting fees and legal costs		4,200	5,200
Deferment of financing costs			2,700
Loss on early extinguishment of debt				$ 3,660
Capitalized Interest
Interest capitalized		1,100	1,100	1,200
Maturities of Long-term Debt [Abstract]
2016		3,000
2017		3,000
2018		3,000
2019		284,138
Total		$ 293,138
Term loan
Long-term debt
Debt Instrument, Maturity Date		Jun. 06, 2019
Long-term debt		$ 293,138	296,138
Interest Rate (as a percent)		5.39%
Quarterly principal payments		$ 800
Excess cash flow used to prepay the debt		0	0	$ 0
Underwriting fees and legal costs	$ 3,400
Maturities of Long-term Debt [Abstract]
Total		$ 293,138	296,138
Term loan \| Minimum
Long-term debt
Percentage of excess cash flow used to prepay the debt		25.00%
Term loan \| Maximum
Long-term debt
Percentage of excess cash flow used to prepay the debt		50.00%
Term loan \| Prime rate
Long-term debt
Variable rate basis		prime rate
Margin (as a percent)		3.00%
Term loan \| Eurocurrency rate
Long-term debt
Interest Rate (as a percent)		5.00%
Variable rate basis		one, two, three or six months Eurocurrency rate
Margin (as a percent)		4.00%
Term loan repaid
Long-term debt
Premium paid on repayment of debt	$ 3,000
Term loan repaid \| Eurocurrency rate
Long-term debt
Variable interest rate floor (as a percent)		1.00%
Revolving credit facility
Long-term debt
Available balance under the facility		$ 30,000
Amounts drawn under the facility		$ 0	$ 0
Revolving credit facility \| Prime rate \| Minimum
Long-term debt
Variable rate basis		prime rate
Margin (as a percent)		3.00%
Revolving credit facility \| Prime rate \| Maximum
Long-term debt
Variable rate basis		prime rate
Margin (as a percent)		6.00%
Revolving credit facility \| Eurocurrency rate \| Minimum
Long-term debt
Variable rate basis		Eurocurrency rate for one, two, three or six month periods
Margin (as a percent)		4.00%
Revolving credit facility \| Eurocurrency rate \| Maximum
Long-term debt
Variable rate basis		Eurocurrency rate for one, two, three or six month periods
Margin (as a percent)		5.50%