Related Party Transactions and Arrangements (Merger and Other Non-routine Transactions) (Details) - Affiliated Entity [Member] - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014
Merger And Acquisition Related Costs [Member]
Related Party Transaction [Line Items]
Related party expenses	$ 0	$ 137,778,000
Merger Related Costs, Strategic Advisory Services [Member]
Related Party Transaction [Line Items]
Related party expenses		27,265,000
Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		72,000
Subordinated Distribution Fees [Member]
Related Party Transaction [Line Items]
Related party expenses		78,244,000
Furniture, Fixtures And Equipment [Member]
Related Party Transaction [Line Items]
Related party expenses		15,800,000
Other Fees And Expenses [Member]
Related Party Transaction [Line Items]
Related party expenses		2,900,000
Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		2,145,000
Post Transaction Support Services [Member]
Related Party Transaction [Line Items]
Related party expenses		11,352,000
ARCT IV Merger [Member] | Merger And Acquisition Related Costs [Member]
Related Party Transaction [Line Items]
Related party expenses		94,213,000
ARCT IV Merger [Member] | Merger Related Costs, Strategic Advisory Services [Member]
Related Party Transaction [Line Items]
Related party expenses		8,400,000
ARCT IV Merger [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		0
ARCT IV Merger [Member] | Subordinated Distribution Fees [Member]
Related Party Transaction [Line Items]
Related party expenses		78,244,000
ARCT IV Merger [Member] | Furniture, Fixtures And Equipment [Member]
Related Party Transaction [Line Items]
Related party expenses		5,800,000
ARCT IV Merger [Member] | Other Fees And Expenses [Member]
Related Party Transaction [Line Items]
Related party expenses		0
ARCT IV Merger [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		417,000
ARCT IV Merger [Member] | Post Transaction Support Services [Member]
Related Party Transaction [Line Items]
Related party expenses		1,352,000
Internalization and Other [Member] | Merger And Acquisition Related Costs [Member]
Related Party Transaction [Line Items]
Related party expenses		20,000,000
Internalization and Other [Member] | Merger Related Costs, Strategic Advisory Services [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Internalization and Other [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Internalization and Other [Member] | Subordinated Distribution Fees [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Internalization and Other [Member] | Furniture, Fixtures And Equipment [Member]
Related Party Transaction [Line Items]
Related party expenses		10,000,000
Internalization and Other [Member] | Other Fees And Expenses [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Internalization and Other [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Internalization and Other [Member] | Post Transaction Support Services [Member]
Related Party Transaction [Line Items]
Related party expenses		10,000,000
Cole Merger [Member] | Merger And Acquisition Related Costs [Member]
Related Party Transaction [Line Items]
Related party expenses		21,815,000
Cole Merger [Member] | Merger Related Costs, Strategic Advisory Services [Member]
Related Party Transaction [Line Items]
Related party expenses		17,115,000
Cole Merger [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		72,000
Cole Merger [Member] | Subordinated Distribution Fees [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Cole Merger [Member] | Furniture, Fixtures And Equipment [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Cole Merger [Member] | Other Fees And Expenses [Member]
Related Party Transaction [Line Items]
Related party expenses		2,900,000
Cole Merger [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		1,728,000
Cole Merger [Member] | Post Transaction Support Services [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Merger And Acquisition Related Costs [Member]
Related Party Transaction [Line Items]
Related party expenses		1,750,000
Multiple-tenant Spin-Off [Member] | Merger Related Costs, Strategic Advisory Services [Member]
Related Party Transaction [Line Items]
Related party expenses		1,750,000
Multiple-tenant Spin-Off [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Subordinated Distribution Fees [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Furniture, Fixtures And Equipment [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Other Fees And Expenses [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Personnel Costs And Other Reimbursements [Member]
Related Party Transaction [Line Items]
Related party expenses		0
Multiple-tenant Spin-Off [Member] | Post Transaction Support Services [Member]
Related Party Transaction [Line Items]
Related party expenses		$ 0