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Overview and Basis of Presentation (Details Textual) (USD $)
Share data in Millions, except Per Share data, unless otherwise specified |
3 Months Ended | 9 Months Ended |
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Oct. 31, 2012
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Oct. 31, 2012
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| Summary of Significant Accounting Policies (Textual) [Abstract] | ||
| Net proceeds | $ 684,620,000 | $ 684,620,000 |
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Common Class A [Member] | IPO [Member]
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| Summary of Significant Accounting Policies (Textual) [Abstract] | ||
| Issued and sold of common share | 26.2 | |
| Offering price | $ 28.00 | $ 28.00 |
| Net proceeds | 684,600,000 | |
| Underwriting discounts and commissions | 44,000,000 | |
| Approximate other offering expenses | $ 4,000,000 | |
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Common Class B [Member] | IPO [Member]
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| Summary of Significant Accounting Policies (Textual) [Abstract] | ||
| Number of shares issued upon conversion | 98.0 | |
| Number of shares issued upon converted | 42.1 |
| X | ||||||||||
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- Definition
The cash outflow for cost incurred directly with the issuance of an equity security. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The cash inflow associated with the amount received from entity's first offering of stock to the public. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Price of a single share of a number of saleable stocks of a company. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This element represents movements in the number of shares included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy. No definition available.
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- Definition
Number of shares issued during the period as a result of the conversion of convertible securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Underwriting discounts and commissions. No definition available.
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