Divestitures (Narrative) (Details) $ in Thousands				3 Months Ended		12 Months Ended
	Mar. 30, 2017 bed	Dec. 31, 2016 USD ($) bed	Dec. 01, 2016 USD ($) bed	Mar. 31, 2017 USD ($) bed	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from sale of hospitals				$ 4,282	$ 0
Impairment of long-lived assets				3,300	0
Gain (loss) on sale of business				$ 870	0
Augusta, Georgia [Member] | Definitive Agreement to Trinity Hospital [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of beds in hospital being sold | bed	231
Centre, Alabama [Member] | Cherokee Medical Center [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Disposal date				Mar. 31, 2017
Number of beds in hospital sold | bed				60
Proceeds from sale of hospitals				$ 4,282
Pre-tax gain (loss) from disposal of discontinued operation				(900)	(1,700)
Gain (loss) on sale of business				$ 800
Centre, Alabama [Member] | Cherokee Medical Center [Member] | Property, Equipment and Capitalized Software [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of long-lived assets						$ 3,900	$ 2,000
Winder, Georgia | Barrow Regional Medical Center [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Disposal date				Dec. 31, 2016
Number of beds in hospital sold | bed		56
Proceeds from sale of hospitals		$ 6,600
Pre-tax gain (loss) from disposal of discontinued operation				$ 600	(2,900)
Gain (loss) on sale of business						(1,200)
Winder, Georgia | Barrow Regional Medical Center [Member] | Property, Equipment and Capitalized Software [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of long-lived assets						4,000
Hamlet, North Carolina [Member] | Sandhills Regional Medical Center [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Disposal date				Dec. 01, 2016
Number of beds in hospital sold | bed			64
Proceeds from sale of hospitals			$ 7,200
Pre-tax gain (loss) from disposal of discontinued operation				$ (600)	$ (600)
Gain (loss) on sale of business						(1,000)
Hamlet, North Carolina [Member] | Sandhills Regional Medical Center [Member] | Property, Equipment and Capitalized Software [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of long-lived assets						$ 4,800