Income tax reconciliation penalties on uncertain tax positions.

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

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-Section S99

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-Subparagraph (SX 210.4-08.(h)(2))

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-Name Regulation S-X (SX)

-Number 210

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Subparagraph (a),(b)

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- Definition

Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

+ References

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- Definition

The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-Number 210

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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Schedule of Effective Tax Rates Vary from Federal Statutory Rates (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Income Tax Disclosure [Abstract]
Earnings Before Income Taxes	$ 44,698	$ 77,866	$ 74,577	$ 55,786	$ 29,767	$ 48,833	$ 58,688	$ 44,516	$ 252,927	$ 181,804	$ 84,096
Income Taxes at Statutory Rate									88,524	63,631	29,434
Increases (Decreases) in Tax Resulting from - State Income Taxes, net									4,582	173	1,346
Increases (Decreases) in Tax Resulting from - Statutory Depletion in Excess of Cost									(4,367)	(3,512)	(3,110)
Increases (Decreases) in Tax Resulting from - Domestic Production Activities Deduction									(6,853)	(3,453)	(1,895)
Increases (Decreases) in Tax Resulting from - Meals and Entertainment Disallowance									647	503	337
Increases (Decreases) in Tax Resulting from - Penalties on Uncertain Tax Positions										213	215
Increases (Decreases) in Tax Resulting from - IRS Settlement									(16,559)
Increases (Decreases) in Tax Resulting from - Other									100	6	25
Provision for Income Taxes									$ 66,074us-gaap_IncomeTaxExpenseBenefit	$ 57,561us-gaap_IncomeTaxExpenseBenefit	$ 26,352us-gaap_IncomeTaxExpenseBenefit
Effective Tax Rate									26.00%	32.00%	31.00%