Summarized Condensed Consolidating Information - Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Assets:
Real estate investments, net	$ 722,217	$ 645,614
Other real estate investments	8,731	8,477
Cash and cash equivalents	4,663	11,467	$ 13,594	$ 25,320
Accounts receivable	2,227	2,342
Prepaid expenses and other assets	2,072	2,083
Deferred financing costs, net	3,598	3,183
Investment in subsidiaries	0	0
Intercompany	0	0
Total assets	743,508	673,166
Liabilities and Equity:
Senior unsecured notes payable, net	254,495	254,229
Mortgage notes payable, net	0	94,676
Accounts payable and accrued liabilities	10,696	9,269
Dividends payable	9,845	7,704
Intercompany	0	0
Total liabilities	379,397	410,878
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	575	477
Additional paid-in capital	516,285	410,217
Cumulative distributions in excess of earnings	(152,749)	(148,406)
Total equity	364,111	262,288		113,462
Total liabilities and equity	743,508	673,166
Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	99,361	0
Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	5,000	45,000
Reportable Legal Entities [Member] | Parent Guarantor [Member]
Assets:
Real estate investments, net	0	0
Other real estate investments	0	0
Cash and cash equivalents	0	0	0	0
Accounts receivable	0	0
Prepaid expenses and other assets	0	0
Deferred financing costs, net	0	0
Investment in subsidiaries	374,247	269,992
Intercompany	0	0
Total assets	374,247	269,992
Liabilities and Equity:
Senior unsecured notes payable, net	0	0
Mortgage notes payable, net		0
Accounts payable and accrued liabilities	291	0
Dividends payable	9,845	7,704
Intercompany	0	0
Total liabilities	10,136	7,704
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	575	477
Additional paid-in capital	516,285	410,217
Cumulative distributions in excess of earnings	(152,749)	(148,406)
Total equity	364,111	262,288
Total liabilities and equity	374,247	269,992
Reportable Legal Entities [Member] | Parent Guarantor [Member] | Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0
Reportable Legal Entities [Member] | Parent Guarantor [Member] | Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0	0
Reportable Legal Entities [Member] | Issuers [Member]
Assets:
Real estate investments, net	337,902	256,209
Other real estate investments	0	0
Cash and cash equivalents	4,663	11,467	13,594	25,320
Accounts receivable	1,134	519
Prepaid expenses and other assets	2,068	2,079
Deferred financing costs, net	3,598	3,183
Investment in subsidiaries	373,655	365,368
Intercompany	18,743	0
Total assets	741,763	638,825
Liabilities and Equity:
Senior unsecured notes payable, net	254,495	254,229
Mortgage notes payable, net		0
Accounts payable and accrued liabilities	8,660	6,258
Dividends payable	0	0
Intercompany	0	63,346
Total liabilities	367,516	368,833
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	0	0
Additional paid-in capital	365,250	266,929
Cumulative distributions in excess of earnings	8,997	3,063
Total equity	374,247	269,992
Total liabilities and equity	741,763	638,825
Reportable Legal Entities [Member] | Issuers [Member] | Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	99,361
Reportable Legal Entities [Member] | Issuers [Member] | Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	5,000	45,000
Reportable Legal Entities [Member] | Combined Subsidiary Guarantors [Member]
Assets:
Real estate investments, net	344,078	348,454
Other real estate investments	8,731	8,477
Cash and cash equivalents	0	0	0	0
Accounts receivable	1,021	1,695
Prepaid expenses and other assets	4	4
Deferred financing costs, net	0	0
Investment in subsidiaries	0	0
Intercompany	70,304	59,160
Total assets	424,138	417,790
Liabilities and Equity:
Senior unsecured notes payable, net	0	0
Mortgage notes payable, net		0
Accounts payable and accrued liabilities	1,673	2,433
Dividends payable	0	0
Intercompany	0	0
Total liabilities	1,673	2,433
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	0	0
Additional paid-in capital	374,660	374,660
Cumulative distributions in excess of earnings	47,805	40,697
Total equity	422,465	415,357
Total liabilities and equity	424,138	417,790
Reportable Legal Entities [Member] | Combined Subsidiary Guarantors [Member] | Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0
Reportable Legal Entities [Member] | Combined Subsidiary Guarantors [Member] | Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0	0
Reportable Legal Entities [Member] | Combined Non-Guarantor Subsidiaries [Member]
Assets:
Real estate investments, net	40,237	40,951
Other real estate investments	0	0
Cash and cash equivalents	0	0	0	0
Accounts receivable	72	128
Prepaid expenses and other assets	0	0
Deferred financing costs, net	0	0
Investment in subsidiaries	0	0
Intercompany	0	4,186
Total assets	40,309	45,265
Liabilities and Equity:
Senior unsecured notes payable, net	0	0
Mortgage notes payable, net		94,676
Accounts payable and accrued liabilities	72	578
Dividends payable	0	0
Intercompany	89,047	0
Total liabilities	89,119	95,254
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	0	0
Additional paid-in capital	(52,899)	(52,899)
Cumulative distributions in excess of earnings	4,089	2,910
Total equity	(48,810)	(49,989)
Total liabilities and equity	40,309	45,265
Reportable Legal Entities [Member] | Combined Non-Guarantor Subsidiaries [Member] | Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0
Reportable Legal Entities [Member] | Combined Non-Guarantor Subsidiaries [Member] | Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0	0
Elimination [Member]
Assets:
Real estate investments, net	0	0
Other real estate investments	0	0
Cash and cash equivalents	0	0	$ 0	$ 0
Accounts receivable	0	0
Prepaid expenses and other assets	0	0
Deferred financing costs, net	0	0
Investment in subsidiaries	(747,902)	(635,360)
Intercompany	(89,047)	(63,346)
Total assets	(836,949)	(698,706)
Liabilities and Equity:
Senior unsecured notes payable, net	0	0
Mortgage notes payable, net		0
Accounts payable and accrued liabilities	0	0
Dividends payable	0	0
Intercompany	(89,047)	(63,346)
Total liabilities	(89,047)	(63,346)
Equity:
Common stock, $0.01 par value; 500,000,000 shares authorized, 47,650,952 and 31,251,157 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	0	0
Additional paid-in capital	(687,011)	(588,690)
Cumulative distributions in excess of earnings	(60,891)	(46,670)
Total equity	(747,902)	(635,360)
Total liabilities and equity	(836,949)	(698,706)
Elimination [Member] | Senior Unsecured Term Loan [Member]
Liabilities and Equity:
Unsecured revolving credit facility	0
Elimination [Member] | Unsecured Revolving Credit Facility [Member]
Liabilities and Equity:
Unsecured revolving credit facility	$ 0	$ 0