Shareholders' Equity (Details) - USD ($)				1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 30, 2015	May. 01, 2015	Jan. 29, 2015	Feb. 28, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Treasury shares (in shares)					1,160,928		1,160,928		264,903
Stock repurchase program, authorized amount					$ 150,000,000		$ 150,000,000
Common stock, par value (in dollars per share)				$ 0.125	$ 0.125		$ 0.125
Dividends declared (in dollars per share)		$ 0.10	$ 0.10		$ 0.1	$ 0.1	$ 0.2	$ 0.1
Common Stock [Member]
Class of Stock [Line Items]
New shares issued				1,100,000
Subsequent Event [Member]
Class of Stock [Line Items]
Dividends declared (in dollars per share)	$ 0.10