Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
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)	122,968,677	122,803,029
Unvested restricted shares (shares)	1,537,717	1,476,132
Treasury Stock (shares)	1,560,544	1,519,360

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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