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The percentage points added to the reference rate to compute the variable rate on the debt instrument under option two of the credit agreement.

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The floor to which the reference rate (e.g., LIBOR) is subject.

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Exercise price per share or per unit of warrants or rights outstanding.

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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 gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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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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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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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 after the fifth 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 fifth 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 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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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.

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Debt, Credit Facility (Details) - USD ($)		3 Months Ended		9 Months Ended
Debt, Credit Facility (Details) - USD ($)	Jun. 03, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Mar. 31, 2015	Aug. 31, 2012
Summarized information about the term loan [Abstract]
Less current portion of term loan		$ (3,067,000)		$ (3,067,000)		$ (7,733,000)
Long-term portion of term loan		20,738,000		20,738,000		71,489,000
Future repayments of the Term Loan, by fiscal year [Abstract]
Total (gain) loss included in net income				3,077,000	$ 2,199,000
Credit Facility [Member]
Credit Facility [Abstract]
Maximum borrowing capacity	$ 125,000,000
Debt instrument, maturity date	Jun. 03, 2020
Quarterly principal payments	$ 781,250
Summarized information about the term loan [Abstract]
Principal amount of term loan		24,219,000		24,219,000		84,500,000
Unamortized debt issuance costs		(414,000)		(414,000)		(5,278,000)
Net carrying amount of term loan		23,805,000		23,805,000		79,222,000
Less current portion of term loan		(3,067,000)		(3,067,000)		(7,733,000)
Long-term portion of term loan		20,738,000		20,738,000		71,489,000
Future repayments of the Term Loan, by fiscal year [Abstract]
2016 - remaining three months		781,000		781,000
2017		3,125,000		3,125,000
2018		3,125,000		3,125,000
2019		3,125,000		3,125,000
2020		3,125,000		3,125,000
Thereafter		$ 10,938,000		$ 10,938,000
Credit Facility [Member] \| Minimum [Member]
Credit Facility [Abstract]
Facility fee on total leverage ratio	0.25%
Credit Facility [Member] \| Maximum [Member]
Credit Facility [Abstract]
Facility fee on total leverage ratio	0.375%
Credit Facility [Member] \| Reference Rate [Member]
Credit Facility [Abstract]
Reference interest rate under option 1, floor	1.50%
Interest rate over reference rate under option 1	1.75%
Interest rate above base rate under option 2	2.00%
Credit Facility [Member] \| LIBOR [Member]
Credit Facility [Abstract]
Reference interest rate under option 1, floor	2.50%
Interest rate over reference rate under option 1	2.75%
Interest rate above base rate under option 2	3.00%
Credit Facility [Member] \| Term Loans [Member]
Credit Facility [Abstract]
Maximum borrowing capacity	$ 25,000,000
Interest rate at end of period		3.00%		3.00%
Credit Facility [Member] \| Revolving Facility [Member]
Credit Facility [Abstract]
Maximum borrowing capacity	100,000,000
Interest rate at end of period		3.64%		3.64%
Future repayments of the Term Loan, by fiscal year [Abstract]
Outstanding balance under revolving loan		$ 7,000,000		$ 7,000,000		0
Amount available under revolving facility		91,513,000		91,513,000
Credit Facility [Member] \| Revolving Facility [Member] \| Letters of Credit [Member]
Credit Facility [Abstract]
Maximum borrowing capacity	$ 15,000,000
Credit Facility [Member] \| Revolving Facility [Member] \| Commercial Letter of Credit [Member]
Future repayments of the Term Loan, by fiscal year [Abstract]
Outstanding balance under revolving loan		1,057,000		1,057,000
Credit Facility [Member] \| Revolving Facility [Member] \| Standby Letters of Credit [Member]
Future repayments of the Term Loan, by fiscal year [Abstract]
Outstanding balance under revolving loan		430,000		430,000
WX Agreement [Member] \| Supplier Warrant [Member]
Future repayments of the Term Loan, by fiscal year [Abstract]
Number of shares that can be purchased under warrants (in shares)							516,129
Exercise price of warrants (in dollars per share)							$ 7.75
Fair value of warrants issued		13,523,000		13,523,000		$ 10,506,000
Total (gain) loss included in net income		$ 1,275,000	$ 1,924,000	$ 3,017,000	$ 2,199,000