Condensed Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Condensed Consolidated Statement of Changes in Stockholders' Equity
Issuance of common stock for employee stock option exercises, shares	34,634
Issuance of common stock for restricted share awards, shares	985,381
Increase in current taxes payable	$ 2.7
Issuance of common stock for the employee stock purchase plan, shares	35,693
Shares Repurchased Under Board Authorization	692,159
Shares repurchased to satisfy minimum statutory withholding tax upon the net settlement of equity awards	365,474