Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net income available to common stockholders — basic and diluted	$ 42,784	$ 38,833	$ 92,638	$ 59,549
Denominator:
Shares used in calculation — basic	548,811,968	525,070,036	545,680,740	523,265,455
Incremental shares attributed to non-vested share-based awards	1,108,245	863,607	1,156,069	925,014
Weighted average common shares outstanding — diluted	549,920,213	525,933,643	546,836,809	524,190,469
Net income per share — basic	$ 0.08	$ 0.07	$ 0.17	$ 0.11
Net income per share — diluted	$ 0.08	$ 0.07	$ 0.17	$ 0.11
2019 Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted EPS		12,553,864		12,553,864
2022 Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted EPS	15,100,443	15,100,443	15,100,443	15,100,443
Non-vested share-based awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted EPS	342,849	0	250,538	9,495