Equity and Dividends (Tables)

12 Months Ended

Dec. 31, 2017

Equity and Dividends [Abstract]

Schedule of Quarterly Dividends Declared and Paid

	Declaration date	Dividend per share		Record date		Total dividends	Payment date
Year ended December 31, 2017:
Fourth quarter 2016	January 23, 2017	$	0.1700	February 10, 2017	$	18,160	March 3, 2017
First quarter 2017	May 4, 2017		0.1700	May 23, 2017		18,188	June 13, 2017
Second quarter 2017	August 4, 2017		0.1700	August 25, 2017		18,210	September 15, 2017
Third quarter 2017	November 8, 2017		0.1700	November 29, 2017		18,227	December 20, 2017
Year ended December 31, 2016:
Fourth quarter 2015	January 15, 2016	$	0.1600	February 12, 2016	$	17,154	March 4, 2016
First quarter 2016	May 9, 2016		0.1600	May 24, 2016		17,022	June 14, 2016
Second quarter 2016	August 5, 2016		0.1700	September 2, 2016		18,127	September 23, 2016
Third quarter 2016	November 8, 2016		0.1700	November 28, 2016		18,156	December 19, 2016
Year ended December 31, 2015:
Fourth quarter 2014	January 12, 2015	$	0.1400	February 13, 2015	$	15,089	March 6, 2015
First quarter 2015	May 7, 2015		0.1400	May 29, 2015		14,955	June 19, 2015
Second quarter 2015	August 6, 2015		0.1600	September 4, 2015		17,147	September 25, 2015
Third quarter 2015	November 5, 2015		0.1600	November 27, 2015		17,149	December 18, 2015