PRO FORMA FINANCIAL INFORMATION (UNAUDITED) - Schedule of Pro Forma Information (Details) - Series of Individually Immaterial Business Acquisitions [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 266,478	$ 264,084
Depreciation and amortization	71,021	71,436
Net income attributable to common stockholders	$ 92,724	$ 85,136
Net income attributable to common stockholders, per:
Basic common share (in dollars per share)	$ 1.49	$ 1.84
Diluted common share (in dollars per share)	$ 1.48	$ 1.82
Weighted-average number of common shares outstanding, basic (in shares)	62,235,014	46,351,544
Weighted-average number of common shares outstanding, diluted (in shares)	62,460,239	46,889,531