Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2016	Dec. 31, 2015
Preferred stock par value (usd per share)	$ 0.01	$ 0.01
Preferred stock outstanding (shares)	5,000,000	5,000,000
Common Stock par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (shares)	200,000,000	200,000,000
Common stock issued (shares)	123,317,742	122,791,729
Unvested restricted shares (shares)	1,407,486	1,211,951
Treasury Stock (shares)	1,497,893	1,378,002

Face amount or stated value per share of common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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