Income Taxes (Deferred Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Allowance for uncollectible accounts	$ 3,276	$ 1,096
Accrued assets and other	36,600	27,537
Share-based compensation	10,710	7,719
Interest on unrecognized tax benefits	113	245
Accrued liabilities and other	4,080	3,931
Medical malpractice	19,035	16,240
Operating and capital loss carryforwards	29,718	22,709
Valuation allowances	(21,814)	(17,457)
Total deferred tax assets	81,718	62,020
Deferred tax liabilities:
Prepaid expenses	1,789	2,435
Property and equipment, principally due to differences in depreciation	16,787	15,235
Goodwill, intangible assets and other, principally due to differences in amortization	762,640	655,358
Total deferred tax liabilities	781,216	673,028
Net deferred tax liabilities	$ 699,498	$ 611,008

The sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset as well as the amount of future tax deductions arising from capital losses in excess of statutory limitations in historical filings, and which can only be utilized if sufficient tax-basis income is generated in future periods and providing tax laws continue to allow such utilization.

No definition available.