Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Preferred stock, shares par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	12,500,000	12,500,000
Common stock, shares par value	$ 0.06	$ 0.06
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	72,289,000	71,817,000
Common stock, shares outstanding	72,289,000	71,817,000
Treasury stock, shares	3,522,000	3,822,000
Series A [Member]
Liquidation preference, per share	$ 25.00	$ 25.00
Preferred stock, shares authorized	0	1,410,000
Preferred stock, shares issued	0	1,408,000
Preferred stock, shares outstanding	0	1,408,000
Series B [Member]
Liquidation preference, per share	$ 25.00	$ 25.00
Preferred stock, shares authorized	10,000,000	7,500,000
Preferred stock, shares issued	7,950,000	5,429,000
Preferred stock, shares outstanding	7,950,000	5,429,000