Earnings per share (EPS) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings per share, Basic EPS [Abstract]:
Net income	$ 81,702	$ 143,764	$ 115,087
Less paid and accrued earnings allocated to Preferred Stock	(21,063)	(17,903)	(11,909)
Net income available to common stockholders	$ 60,639	$ 125,861	$ 103,178
Weighted average number of common shares, basic and diluted	77,243,252	75,027,474	74,800,000
Earnings per common share, basic and diluted	$ 0.79	$ 1.68	$ 1.38

No definition available.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

No definition available.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=51831255

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Topic 260
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-Section 50
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

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- Definition

Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

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- Definition

Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

+ References

No definition available.

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