EPS Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income	$ 88,857	$ 83,395
Dividends declared on preferred stock ($0.46875 per share)	(3,750)	(3,750)
Dividends, dividend equivalents and undistributed earnings allocated to participating securities	(256)	(219)
Net income to common stockholders - basic and diluted	$ 84,851	$ 79,426
Denominator:
Weighted average common shares for basic and diluted earnings per share (in shares)	450,358	398,317
Basic and diluted earnings per share (in dollars per share)	$ 0.19	$ 0.20
Anti-dilutive securities excluded from diluted earnings per share calculations (in shares)	2,400
RSUs
Denominator:
Weighted average grant date fair value (in dollars per share)	$ 7.49

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period) and after allocation of earnings to participating securities.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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