Investments	6 Months Ended
Jun. 30, 2011
Investments [Abstract]
Investments	(4) Investments *Short-term Investments* Short-term investments are comprised solely of bank certificates of deposit denominated in U.S. dollars with original maturities in excess of three months and represent the investment of excess cash that is available for current operations. The Company recorded these investments on its balance sheet at cost based on its intent and ability to hold these investments to maturity. These short-term investments were purchased at a cost, which approximates fair value based on Level 1 inputs, of $80.0 million and have scheduled maturities through January 2012. During the second quarter of 2011, the Company liquidated $41.0 million of its original investment to cover the working capital required to bridge the funding of the Company’s multi-client projects. *Long-term Investment* In May 2011, the Company purchased a convertible note from a private U.S-based technology company. The principal amount of the note is $6.5 million and bears interest at a rate of 4% per annum. The maturity date of the note is two years; however, the note will automatically convert into shares of common stock of the investee on the earlier to occur of (a) the maturity date of the note and (b) the date funds are invested into the investee by any venture capital firm or other investor. Upon the occurrence of a conversion event, the note will convert into a number of shares of common stock equal to 15% of the total post-conversion outstanding shares of common stock of the investee. The investee does not have the right to prepay any principal on the note without the Company’s consent; therefore, it is expected that the note will automatically convert within two years. Interest on the note will be paid in cash upon the maturity date, or conversion, if sooner. The Company classifies its investment as available-for-sale and has recorded the fair value of this investment as a noncurrent asset included in other assets on its consolidated balance sheet with unrealized gains and losses reflected in accumulated other comprehensive income until realized. The Company uses a market approach to estimate the fair value of its investment in the convertible debt security using Level 3 inputs, such as financial information available related to the investee and the length of time since the investment was purchased in May 2011. As of June 30, 2011, the fair value of this investment was $6.5 million with no unrealized gains or losses recorded in accumulated other comprehensive income.

(4) Investments

Short-term Investments

Short-term investments are comprised solely of bank certificates of deposit denominated in U.S. dollars with original maturities in excess of three months and represent the investment of excess cash that is available for current operations. The Company recorded these investments on its balance sheet at cost based on its intent and ability to hold these investments to maturity. These short-term investments were purchased at a cost, which approximates fair value based on Level 1 inputs, of $80.0 million and have scheduled maturities through January 2012. During the second quarter of 2011, the Company liquidated $41.0 million of its original investment to cover the working capital required to bridge the funding of the Company’s multi-client projects.

Long-term Investment

In May 2011, the Company purchased a convertible note from a private U.S-based technology company. The principal amount of the note is $6.5 million and bears interest at a rate of 4% per annum. The maturity date of the note is two years; however, the note will automatically convert into shares of common stock of the investee on the earlier to occur of (a) the maturity date of the note and (b) the date funds are invested into the investee by any venture capital firm or other investor. Upon the occurrence of a conversion event, the note will convert into a number of shares of common stock equal to 15% of the total post-conversion outstanding shares of common stock of the investee. The investee does not have the right to prepay any principal on the note without the Company’s consent; therefore, it is expected that the note will automatically convert within two years. Interest on the note will be paid in cash upon the maturity date, or conversion, if sooner.

The Company classifies its investment as available-for-sale and has recorded the fair value of this investment as a noncurrent asset included in other assets on its consolidated balance sheet with unrealized gains and losses reflected in accumulated other comprehensive income until realized. The Company uses a market approach to estimate the fair value of its investment in the convertible debt security using Level 3 inputs, such as financial information available related to the investee and the length of time since the investment was purchased in May 2011. As of June 30, 2011, the fair value of this investment was $6.5 million with no unrealized gains or losses recorded in accumulated other comprehensive income.