Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

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

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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 effective interest rate at the end of the reporting period.

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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 and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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Amount of long-term debt and capital lease obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

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6. Long-Term Debt (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2010
Debt Instrument [Line Items]
Debt and Capital Lease Obligations	$ 435,900,000us-gaap_DebtAndCapitalLeaseObligations	$ 436,000,000us-gaap_DebtAndCapitalLeaseObligations
Less Current Maturities	(264,000)	(265,000)
Long-term debt, net of current maturities	435,661,000	435,710,000
Unsecured Debt [Member] \| Senior Notes 4.875% [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.875%
Long-term debt	423,500,000	423,500,000	422,600,000
Debt Instrument, Interest Rate, Effective Percentage			4.946%
Face amount of debt sold			425,000,000
Capital Lease Obligations [Member] \| Debt 6 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	12,400,000	12,500,000
Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity	200,000,000
Outstanding borrowings	0
Line of Credit Facility, Interest Rate at Period End	1.52%
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity	$ 5,000,000