Common Stock (Tables)

12 Months Ended

Dec. 31, 2015

A reconciliation of the changes in common shares issued is as follows:



	Year ended December 31,
	2015	2014
Shares issued at the beginning of the year	54,633,726	58,265,911
Issued in acquisitions	60,024	99,681
Issued in payment of accrued liability	—	27,101
Issued upon exercise of warrants	—	1,277,250
Issued as restricted stock award grants	758,904	525,120
Issued upon exercise of stock options	767,560	311,954
Retirement of treasury shares	—	(5,873,291	)
Shares issued at the end of the year	56,220,214	54,633,726

Stock option activity for the year ended December 31, 2015 is as follows:



Options	Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding as of January 1, 2015	1,544,960		$	4.81
Exercised	(767,560	)	1.79
Forfeited	—		—
Expired	—		—
Outstanding as of December 31, 2015	777,400		$	7.80	1.31	$	2,828,951
Vested or expected to vest at
December 31, 2015	777,400		$	7.80	1.31	$	2,828,951
Options exercisable as of
December 31, 2015	777,400		$	7.80	1.31	$	2,828,951

Restricted stock share activity for the year ended December 31, 2015 is as follows:



Restricted Stock Shares	Shares		Weighted- Average Fair Value at Date of Grant
Non-vested at January 1, 2015	826,518		$	18.78
Granted	406,650		16.15
RSAs converted from 2014 restricted stock units	352,254		24.66
Vested	(653,211	)	20.90
Forfeited	(32,995	)	22.72
Non-vested at December 31, 2015	899,216		$	18.21

Restricted stock unit share activity for the year ended December 31, 2015 is as follows:



Restricted Stock Unit Shares	Shares		Weighted- Average Fair Value at Date of Grant
RSU share equivalents at January 1, 2015	352,254		$	24.66
2014 RSUs converted to RSAs in 2015	(352,254	)	24.66
Share equivalents earned in 2015	386,049		21.96
RSU share equivalents at December 31, 2015	386,049		$	21.96