Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Assets
Related party accounts receivable		$ 11.2	$ 4.2
Fair value of unconsolidated investments		1,107.4	662.6
Accumulated deprecation and amortization		703.2	623.6
Assets	[1]	7,304.5	7,381.8
Real estate and acquired in place lease values, net of accumulated depreciation and amortization		5,080.2	5,702.5
Liabilities
Liabilities	[1]	$ 5,585.3	$ 5,950.6
Stockholders' Equity Attributable to Parent [Abstract]
Cumulative preferred stock, par value (in dollars per shares)		$ 0.0001
Cumulative preferred stock, shares authorized (in shares)		1,000,000
Cumulative preferred stock, liquidation preference (in dollars per share)		$ 1,000
Cumulative preferred stock, shares outstanding (in shares)		300,000
Common stock par value (in dollars per share)		$ 0.001	$ 0.001
Common stock authorized (in shares)		200,000,000	200,000,000
Common stock issued (in shares)		142,283,109	143,205,394
Common stock outstanding (in shares)		142,283,109	143,205,394
Variable Interest Entity, Primary Beneficiary [Member]
Assets
Assets		$ 267.5	$ 657.8
Cash held by consolidated investments		10.3	31.6
Real estate and acquired in place lease values, net of accumulated depreciation and amortization		243.5	602.5
Liabilities
Liabilities		219.7	317.4
Variable Interest Entity, Primary Beneficiary [Member] | Investment Debt [Member]
Liabilities
Debt		$ 206.0	$ 283.6

[1] The assets and liabilities as of December 31, 2019 include $267.5 million (including cash held by consolidated investments of $10.3 million and real estate and acquired in place lease values, net of accumulated depreciation and amortization of $243.5 million) and $219.7 million (including investment debt of $206.0 million), respectively, from consolidated variable interest entities ("VIEs"). The assets and liabilities as of December 31, 2018 include $657.8 million (including cash held by consolidated investments of $31.6 million and real estate and acquired in place lease values, net of accumulated depreciation and amortization of $602.5 million) and $317.4 million (including investment debt of $283.6 million), respectively, from VIEs. These assets can only be used to settle obligations of the consolidated VIEs, and the liabilities do not have recourse to the Company.