Share-Based Compensation (Details 1) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Options outstanding (shares)	845,000	1,031,000	2,181,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life	2 years 256 days	3 years 256 days
Options Exercisable, Exercisable (shares)	414,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 17.51
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	0	0	462,229
$15.98 - $18.94
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Shares authorized under stock option plans, lower price range (in dollars per share)	$ 15.98
Shares authorized under stock option plans, upper price range (in dollars per share)	$ 18.94
Options outstanding (shares)	845,285
Options Outstanding, Weighted-Avg. Remaining Contractual Life	2 years 256 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 17.54
Options Exercisable, Exercisable (shares)	414,308
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 17.51