Stockholders' Equity Transactions (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Jun. 30, 2012	May 31, 2008
Stockholders' Equity (Textual) [Abstract]
Shares of common stock authorized to be repurchased			4.0
Remaining shares to be repurchased		3.9
Number of restricted stock units cancelled in payment of taxes owed by employees	0.2
Value of restricted stock units cancelled	$ 3.1