Consolidated Statements Of Shareholders' Equity (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Statement of Stockholders' Equity [Abstract]
Issuance of common stock from stock-based compensation awards, tax benefit	$ 3,895	$ 18,900

Adjustment to additional paid in capital related to the net effect of excess tax benefits and tax deficiencies associated with an equity-based compensation plan other than an employee stock ownership plan (ESOP).

No definition available.

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Balance Type:	credit
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