Equity Method Investment in INOVA Geophysical (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Equity Method Investment Summarized Financial Information Balance Sheets
Current assets	$ 138,401	$ 104,291
Non-current assets	101,280	108,039
Current liabilities	78,241	38,849
Non-current liabilities	9,290	25,701
Equity	$ 152,150	$ 147,780

The amount of current assets reported by an equity method investment of the entity.

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+ Details

- Definition

The amount of current liabilities reported by an equity method investment of the entity.

+ References

+ Details

- Definition

Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

+ References+ Details

- Definition

The amount of noncurrent assets reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent liabilities reported by an equity method investment of the entity.

+ References

+ Details