Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
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	91,319,000	85,316,000
Common stock, shares outstanding	91,319,000	85,316,000
Treasury stock, shares	3,367,000	3,264,000
Series B [Member]
Preferred stock, shares authorized	3,450,000	10,000,000
Liquidation preference, per share	$ 25.00	$ 25.00
Preferred stock, shares issued	3,450,000	7,950,000
Preferred stock, shares outstanding	3,450,000	7,950,000
Series C [Member]
Preferred stock, shares authorized	6,050,000	0
Liquidation preference, per share	$ 25.00	$ 25.00
Preferred stock, shares issued	3,000,000	0
Preferred stock, shares outstanding	3,000,000	0