Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2012

Accounting Policies [Abstract]

Net income for purposes of determining basic EPS

Net income for purposes of determining basic EPS was as follows:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2012			2011			2012			2011
Net income	$	17,932		$	17,549		$	14,137		$	67,223
Income attributable to participating securities	(350		)	(359		)	(284		)	(1,390		)
Net income available to common stockholders	$	17,582		$	17,190		$	13,853		$	65,833

Net income (loss) for purposes of determining diluted EPS

Net income for purposes of determining diluted EPS was as follows:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2012			2011			2012			2011
Net income	$	17,932		$	17,549		$	14,137		$	67,223
Expense attributable to 3.875% Variable Interest Senior Convertible Debentures	—			680			—			4,608
Expense attributable to 6.75% Variable Interest Senior Convertible Note	—			—			—			2,994
Income attributable to participating securities	(350		)	(373		)	(284		)	(1,548		)
Net income available to common stockholders	$	17,582		$	17,856		$	13,853		$	73,277

Basic and diluted EPS calculation shares

Basic and diluted EPS were calculated using the following shares:

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2012	2011	2012	2011
Weighted-average shares for basic EPS	85,299,645	82,965,473	83,891,231	82,472,035
Plus incremental shares related to stock options and non-vested restricted stock	165,723	640,507	191,974	527,305
Plus incremental shares related to convertible debt	—	6,479,204	—	10,952,616
Weighted-average shares for fully diluted EPS	85,465,368	90,085,184	84,083,205	93,951,956

Outstanding shares not included in the computation of diluted EPS

The following stock options, non-vested restricted stock and shares issuable upon the conversion of convertible debt were outstanding during the three and nine months ended September 30, 2012 and 2011 but were not included in the computation of diluted EPS because the effect was anti-dilutive.

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2012		2011		2012		2011
Number of stock options	N/A		11,088		N/A		11,088
Weighted-average exercise price	N/A		$	22.70	N/A		$	22.70
Weighted-average shares of non-vested restricted stock	3,500		N/A		3,500		N/A
Weighted-average expense per share	17.12		N/A		17.12		N/A
Weighted-average number of shares issuable upon   conversion of debt	15,929,565		11,701,241		17,316,315		7,660,326
Weighted-average conversion price	$	13.95	$	13.47	$	14.05	$	14.04