Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
|
3 Months Ended | 12 Months Ended | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2012
Rigs
Country
|
Sep. 30, 2012
|
Jun. 30, 2012
|
Mar. 31, 2012
|
Dec. 31, 2011
|
Sep. 30, 2011
|
Jun. 30, 2011
|
Mar. 31, 2011
|
Dec. 31, 2012
Customer
Rigs
Country
|
Dec. 31, 2011
|
Dec. 31, 2010
|
|
Revenue, Major Customer [Line Items] | |||||||||||
Number of countries with operations | 12 | 12 | |||||||||
Number of countries in which Entity has operated since inception | 50 | 50 | |||||||||
Barge drilling rigs | 14 | 14 | |||||||||
Land rings | 24 | 24 | |||||||||
Percentage accounted for under the equity method | 50.00% | 50.00% | |||||||||
Reimbursement cost | $ 44,900,000 | $ 64,200,000 | $ 40,100,000 | ||||||||
Foreign currency translation impact over net income and retained earnings | 6,400,000 | ||||||||||
Collection period | 90 days | ||||||||||
Capitalized interest costs of construction of rigs | 10,200,000 | 19,300,000 | 13,500,000 | ||||||||
Net assets held for sale including current asset | 11,550,000 | 5,315,000 | 11,550,000 | 5,315,000 | |||||||
Consumed and replenished period | 1 year | ||||||||||
Rate of recognized income tax position being realized | 50.00% | ||||||||||
Deposits in domestic bank | 12,200,000 | 10,200,000 | 12,200,000 | 10,200,000 | |||||||
Deposits in foreign banks | 34,500,000 | 38,400,000 | 34,500,000 | 38,400,000 | |||||||
Number of major customer | 2 | ||||||||||
Construction revenue | 335,500,000 | 325,900,000 | |||||||||
Contract margin | 16,405,000 | 34,038,000 | 46,440,000 | 54,018,000 | 44,399,000 | 49,966,000 | 40,797,000 | 21,204,000 | 150,901,000 | 156,366,000 | 73,167,000 |
Share-based awards vesting period | 3 years | ||||||||||
Liberty Rig Construction Contract [Member]
|
|||||||||||
Revenue, Major Customer [Line Items] | |||||||||||
Contract margin | $ 11,700,000 | ||||||||||
Exxon Neftegas Limited (ENL) [Member]
|
|||||||||||
Revenue, Major Customer [Line Items] | |||||||||||
Percentage of revenue from major customer | 11.80% | ||||||||||
Dowell Schlumberger [Member]
|
|||||||||||
Revenue, Major Customer [Line Items] | |||||||||||
Percentage of revenue from major customer | 10.40% |