Significant Accounting Policies	3 Months Ended
Mar. 31, 2012
Significant Accounting Policies [Abstract]
Significant Accounting Policies	SIGNIFICANT ACCOUNTING POLICIES We, the management of National Health Investors, Inc., ("NHI" or the "Company") believe that the unaudited condensed consolidated financial statements to which these notes are attached include all normal, recurring adjustments which are necessary to fairly present the condensed consolidated financial position, results of operations and cash flows of NHI in all material respects. The Condensed Consolidated Balance Sheet at December 31, 2011 has been derived from the audited consolidated financial statements at that date. We assume that users of these condensed consolidated financial statements have read or have access to the audited December 31, 2011 consolidated financial statements and Management's Discussion and Analysis of Financial Condition and Results of Operations and that the adequacy of additional disclosure needed for a fair presentation, except in regard to material contingencies, may be determined in that context. Accordingly, footnotes and other disclosures which would substantially duplicate those contained in our most recent Annual Report on Form 10-K for the year ended December 31, 2011 have been omitted. This condensed consolidated financial information is not necessarily indicative of the results that may be expected for a full year for a variety of reasons including, but not limited to, acquisitions and dispositions, changes in interest rates, rents and the timing of debt and equity financings. For a better understanding of NHI and its condensed consolidated financial statements, we recommend reading these condensed consolidated financial statements in conjunction with the audited consolidated financial statements for the year ended December 31, 2011, which are included in our 2011 Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission, a copy of which is available at our web site: www.nhireit.com. Fair Value Measurements – Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. A three-level fair value hierarchy is required to prioritize the inputs used to measure fair value. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities. Level 2 — Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs. Federal Income Taxes – We intend at all times to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. We will not be subject to U.S. federal income tax, provided that we continue to qualify as a REIT and make distributions to stockholders equal to or in excess of our taxable income. Accordingly, no provision for federal income taxes has been made in the condensed consolidated financial statements. Our failure to continue to qualify under the applicable REIT qualification rules and regulations would have a material adverse impact on our financial position, results of operations and cash flows. Earnings and profits, which determine the taxability of dividends to stockholders, differ from net income reported for financial reporting purposes due primarily to differences in the basis of assets, estimated useful lives used to compute depreciation expense, gains on sales of real estate, non-cash compensation expense and recognition of commitment fees. Our tax returns filed for years beginning in 2009 are subject to examination by taxing authorities. We classify interest and penalties related to uncertain tax positions, if any, in our condensed consolidated financial statements as a component of income tax expense. Discontinued Operations and Assets Held for Sale - We have reclassified for all periods presented the operations of the facilities meeting the accounting criteria as either being sold or held for sale as discontinued operations in the Condensed Consolidated Statements of Comprehensive Income. Long-lived assets classified as held for sale are reported separately in the Condensed Consolidated Balance Sheets. Mortgage Notes Receivable – We evaluate the carrying values of our mortgage notes receivable on an instrument-by-instrument basis. On a quarterly basis, we review our notes receivable for recoverability when events or circumstances, including the non-receipt of contractual principal and interest payments, significant deteriorations of the financial condition of the borrower and significant adverse changes in general economic conditions, indicate that the carrying amount of the note receivable may not be recoverable. If necessary, an impairment is measured as the amount by which the carrying amount exceeds the discounted cash flows expected to be received under the note receivable or, if foreclosure is probable, the fair value of the collateral securing the note receivable. Mortgage Interest and Rental Income - We identify loans and leases as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to mortgage interest and rental income on non-performing loans or leased real estate properties is to recognize rental or mortgage interest income in the period when the related cash is received. Once classified as non-performing, we continue this policy through the life of the affected loan or lease. New Accounting Pronouncements - In the first quarter of our fiscal year ending December 31, 2012 we adopted ASU 2011-05, Presentation of Comprehensive Income (“ASU 2011-05”). ASU 2011-05 eliminates the option to present the components of other comprehensive income as part of the statement of changes in stockholders' equity. ASU 2011-05 does not change the items that must be reported in other comprehensive income or when an item of other comprehensive income must be reclassified to net income. Accordingly, our adoption of this guidance is now incorporated retrospectively in our Condensed Consolidated Statements of Comprehensive Income. The adoption of ASU 2011-05 did not have a material impact on our condensed consolidated financial statements. Reclassifications – Certain reclassifications have been made to the prior period financial statements to conform to the current period presentation.

SIGNIFICANT ACCOUNTING POLICIES

We, the management of National Health Investors, Inc., ("NHI" or the "Company") believe that the unaudited condensed consolidated financial statements to which these notes are attached include all normal, recurring adjustments which are necessary to fairly present the condensed consolidated financial position, results of operations and cash flows of NHI in all material respects. The Condensed Consolidated Balance Sheet at December 31, 2011 has been derived from the audited consolidated financial statements at that date. We assume that users of these condensed consolidated financial statements have read or have access to the audited December 31, 2011 consolidated financial statements and Management's Discussion and Analysis of Financial Condition and Results of Operations and that the adequacy of additional disclosure needed for a fair presentation, except in regard to material contingencies, may be determined in that context. Accordingly, footnotes and other disclosures which would substantially duplicate those contained in our most recent Annual Report on Form 10-K for the year ended December 31, 2011 have been omitted. This condensed consolidated financial information is not necessarily indicative of the results that may be expected for a full year for a variety of reasons including, but not limited to, acquisitions and dispositions, changes in interest rates, rents and the timing of debt and equity financings. For a better understanding of NHI and its condensed consolidated financial statements, we recommend reading these condensed consolidated financial statements in conjunction with the audited consolidated financial statements for the year ended December 31, 2011, which are included in our 2011 Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission, a copy of which is available at our web site: www.nhireit.com.

Fair Value Measurements – Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. A three-level fair value hierarchy is required to prioritize the inputs used to measure fair value. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.

Federal Income Taxes – We intend at all times to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. We will not be subject to U.S. federal income tax, provided that we continue to qualify as a REIT and make distributions to stockholders equal to or in excess of our taxable income. Accordingly, no provision for federal income taxes has been made in the condensed consolidated financial statements. Our failure to continue to qualify under the applicable REIT qualification rules and regulations would have a material adverse impact on our financial position, results of operations and cash flows.

Earnings and profits, which determine the taxability of dividends to stockholders, differ from net income reported for financial reporting purposes due primarily to differences in the basis of assets, estimated useful lives used to compute depreciation expense, gains on sales of real estate, non-cash compensation expense and recognition of commitment fees.

Our tax returns filed for years beginning in 2009 are subject to examination by taxing authorities. We classify interest and penalties related to uncertain tax positions, if any, in our condensed consolidated financial statements as a component of income tax expense.

Discontinued Operations and Assets Held for Sale - We have reclassified for all periods presented the operations of the facilities meeting the accounting criteria as either being sold or held for sale as discontinued operations in the Condensed Consolidated Statements of Comprehensive Income. Long-lived assets classified as held for sale are reported separately in the Condensed Consolidated Balance Sheets.

Mortgage Notes Receivable – We evaluate the carrying values of our mortgage notes receivable on an instrument-by-instrument basis. On a quarterly basis, we review our notes receivable for recoverability when events or circumstances, including the non-receipt of contractual principal and interest payments, significant deteriorations of the financial condition of the borrower and significant adverse changes in general economic conditions, indicate that the carrying amount of the note receivable may not be recoverable. If necessary, an impairment is measured as the amount by which the carrying amount exceeds the discounted cash flows expected to be received under the note receivable or, if foreclosure is probable, the fair value of the collateral securing the note receivable.

Mortgage Interest and Rental Income - We identify loans and leases as non-performing if a required payment is not received within 30 days of the date it is due. Our policy related to mortgage interest and rental income on non-performing loans or leased real estate properties is to recognize rental or mortgage interest income in the period when the related cash is received. Once classified as non-performing, we continue this policy through the life of the affected loan or lease.

New Accounting Pronouncements - In the first quarter of our fiscal year ending December 31, 2012 we adopted ASU 2011-05, Presentation of Comprehensive Income (“ASU 2011-05”). ASU 2011-05 eliminates the option to present the components of other comprehensive income as part of the statement of changes in stockholders' equity. ASU 2011-05 does not change the items that must be reported in other comprehensive income or when an item of other comprehensive income must be reclassified to net income. Accordingly, our adoption of this guidance is now incorporated retrospectively in our Condensed Consolidated Statements of Comprehensive Income. The adoption of ASU 2011-05 did not have a material impact on our condensed consolidated financial statements.

Reclassifications – Certain reclassifications have been made to the prior period financial statements to conform to the current period presentation.