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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-Term Debt (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Common Stock, par value		$ 0.01		$ 0.01
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 165,900
Debt extinguishment gains		3,223	$ 0
Letters of Credit Outstanding, Amount		25,000
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 2,700
Seven Point Three Seven Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.375%
Debt Instrument, Repurchased Face Amount		$ 13,900
Debt Instrument, Repurchase Amount		11,900
Debt extinguishment gains		$ 1,800
Three Point Zero Percentage Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.00%	3.00%
Two Point Five Percentage Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.50%	2.50%
Debt Instrument, Repurchased Face Amount		$ 20,200
Debt Instrument, Repurchase Amount		18,900
Debt extinguishment gains		1,400
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Repayments of long-term debt		2,200
Proceeds from Issuance of Debt		7,400
Debt Issuance Cost		100
Sea-Vista [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit		5,000
Line of Credit Facility, Current Borrowing Capacity		82,000
Sea-Vista [Member] \| Term A-1 Loan [Member]
Debt Instrument [Line Items]
Repayments of long-term debt		1,000
Illinois Corn Processing LLC [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity		15,500
Long-term Debt [Member] \| Two Point Five Percentage Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount		17,500
Additional Paid-In Capital [Member] \| Two Point Five Percentage Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount		$ 1,400
Subsequent Event [Member] \| Sea-Vista [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit	$ 32,000